Aspirating IP Limited v Vision Systems Limited

Introduction 1 Before the Court are two appeals and a cross appeal under s 60 of the Patents Act 1990 (Cth) ("the Act"). In the case of each appeal the applicant is Aspirating IP Limited and the respondent is Vision Systems Ltd. The appeals relate to an opposition to the grant of a standard patent. The respondent has also filed a notice of contention in one of the appeals. 2 On 1 August 1994, Airsense Technology Limited ("Airsense Technology") filed International Application No PCT/GB 1994/001680 with the United Kingdom Patent Office as receiving office. The Application claimed priority from the filing date of British Patent Application No GB 93157790 being 30 July 1993. The patent application was advertised accepted on 2 April 1998. On 1 July 1998, the respondent filed a notice of opposition. A statement of grounds and particulars of the opposition were filed on 1 October 1998. That document was amended on several occasions. On 4 August 1999, Airsense Technology made a request to amend the application. There was no opposition to the proposed amendments which involved the substitution of all the claims with new claims 1-7. Allowance of the request was advertised on 6 April 2000. Airsense Technology's invention involved a smoke detection system and the seven claims were as follows: "(1) A method of detecting content of an impurity in a stream of air flowing through main duct means in the form of sampling duct means of a smoke detection system, comprising causing only part of said stream to flow into secondary duct means, filtering said part of said stream through a particles filter disposed in said secondary duct means, and detecting, by detecting means downstream of said filter, the content of said impurity in the air in said secondary duct means. (2) A method according to claim 1, wherein the whole of said stream passes through a detection module through which extends said main duct means and which contains said secondary duct means, said filter and said detecting means. (3) Apparatus for detecting content of an impurity in a stream of air, comprising main duct means in the form of sampling duct means of a smoke detection system and through which said stream can flow, secondary duct means communicating with said main duct means for receiving only part of the said stream, detecting means serving to detect the content of the impurity in the air in said secondary ducts means, and a particles filter disposed in said secondary duct means and upstream of said detecting means for said part of said stream to flow through said filter. (4) Apparatus according to claim 3, wherein said main duct means extends through a detection module through which extends said main duct means and which contains said secondary duct means, said filter and said detecting means. (5) Apparatus according to claim 3 or 4, wherein said powered means is located upstream of said secondary duct means. (6) A method of detecting the content of an impurity in a stream of air, substantially as hereinbefore described with reference to the accompanying drawings. (7) Apparatus for detecting the content of an impurity in a stream of air, substantially as hereinbefore described with reference to the accompanying drawings." 3 The Patent application No 689484 and the opposition thereto under s 59 of the Act were considered by a delegate of the Commissioner of Patents. On 2 March 2, the delegate published his decision. The delegate reached the following conclusions: 1. Airsense Technology was not disqualified from entitlement to the invention by reason of the association of its staff with IEI (UK) Pty Ltd ("IEI (UK)"), a company which was a subsidiary of IEI (Aust) Pty Ltd ("IEI (Aust)"). 2. The invention in claims 1 and 3 did not involve an inventive step. 3. There was a problem with the fair basis and clarity, and consequent entitlement to the claimed priority date, of claim 5. An amendment to bring the description of the invention in line with the claim would not remedy the situation. Claim 5 was clearly flawed as it stood. 4. There was patentable subject matter in the specification and a period of 60 days from the date of the decision would be allowed for Airsense Technology to claim that subject matter in the claims. If suitable amendments were not proposed within that time, the application would be refused. 4 Airsense Technology appealed to this Court against those parts of the delegate's decision which were unfavourable to it (SAD 59 of 2005). The appeal was brought pursuant to s 60(4) of the Act and Airsense Technology sought orders that the decision of the Commissioner through her delegate be quashed or be set aside, that the appeal be allowed, and that the opposition be dismissed, and the opposed application be allowed to proceed to grant. 5 Vision Systems Limited ("Vision Systems") filed a Notice of Cross-appeal and Notice of Contention pursuant to O 58 r 5A of the Federal Court Rules. This document was amended on more than one occasion and the document before me was a Further Amended Notice of Cross-appeal and Notice of Contention dated 23 September 2009. 6 In addition to its appeal to this Court, Airsense Technology sought to amend its claims. On 2 May 2005 it sought the Commissioner's leave to amend pursuant to s 104 of the Act. In that request, Airsense Technology sought to amend claim 5, but it did not seek to amend claim 1 or claim 3. In addition, Airsense Technology sought to introduce a number of additional claims that had not been considered by the delegate in the hearing leading to his decision under s 60(1) of the Act. The amendments as then proposed were not allowed by the Commissioner. The applicant made further requests for leave to amend under s 104 of the Act and, in the result, on 26 September 2006, the amendments in their then form were allowed. 7 The claims for the invention, as allowed by the Commissioner on 26 September 2006, were as follows: "1. A method of detecting content of an impurity in a stream of air flowing through main duct means in the form of sampling duct means of a smoke detection system, comprising causing only part of said stream to flow into secondary duct means, filtering said part of said stream through a particles filter disposed in said secondary duct means, and detecting, by detecting means downstream of said filter, the content of said impurity in the air in said secondary duct means. 2. A method according to claim 1, wherein the whole of said stream passes through a detection module through which extends said main duct means and which contains said secondary duct means, said filter and said detecting means. 3. Apparatus for detecting content of an impurity in a stream of air, comprising main duct means in the form of sampling duct means of a smoke detection system and through which said stream can flow, secondary duct means communicating with said main duct means for receiving only part of said stream, detecting means serving to detect the content of the impurity in the air in said secondary duct means, and a particles filter disposed in said secondary duct means and upstream of said detecting means for said part of said stream to flow through said filter. 4. A method of detecting content of a particulate impurity in a stream of air flowing through main duct means in the form of sampling duct means of a smoke detection system, comprising causing only part of said stream to flow into secondary duct means, filtering said part of said stream through a particles filter disposed in said secondary duct means and employed to remove larger particles than those intended to be detected, and detecting, by detecting means downstream of said filter, the content of said impurity in the air in said secondary duct means. 5. A method according to claim 4, wherein the whole of said stream passes through a detection module through which extends said main duct means and which contains said secondary duct means, said filter and said detecting means. 6. Apparatus for detecting content of a particulate impurity in a stream of air, comprising main duct means in the form of sampling duct means of a smoke detection system and through which said stream can flow, secondary duct means communicating with said main duct means for receiving only part of said stream, detecting means serving to detect the content of the particulate impurity in the air in said secondary duct means, and a particles filter disposed in said secondary duct means, and upstream of said detecting means for said part of said stream to flow through said filter to remove from said part of said stream larger particles than those intended to be detected. 7. Apparatus according to claim 6, wherein said main duct means extends through a detection module which contains said secondary duct means, said filter and said detecting means. 8. Apparatus according to claim 6 or 7 wherein mechanical powered means is located in said main duct means and upstream of said secondary duct means for forcing air through said main duct means, said secondary duct means, said particles filter and said detecting means. 9. Apparatus according to any one of claims 6 to 8, wherein said sampling duct means includes a plurality of sampling pipes. 10. Apparatus according to any one of claims 6 to 9, wherein said detecting means is a single detector. 11. Apparatus according to claim 10, wherein said detector includes a tubular housing. 12. Apparatus according to any one of claims 6 to 11, wherein said detecting means comprises a semiconductor optical emitter. 13. Apparatus for detecting content of an impurity in a stream of air, comprising main duct means in the form of sampling duct means of a smoke detection system and through which said stream can flow, secondary duct means communicating with said main duct means for receiving only part of said stream, detecting means serving to detect the content of the impurity in the air in said secondary duct means, and a particles filter disposed in said secondary duct means and upstream of said detecting means for said part of said stream to flow through said filter, in which apparatus said main duct means extends through a detection module which contains said secondary duct means, said filter and said detecting means. 14. Apparatus according to claim 13, wherein mechanical powered means is located in said main duct means and upstream of said secondary duct means for forcing air through said main duct means, said secondary duct means, said particles filter and said detecting means. 15. Apparatus according to claim 13 or 14, wherein said sampling duct means includes a plurality of sampling pipes. 16. Apparatus according to any one of claims 13 to 15, wherein said detecting means is a single detector. 17. Apparatus according to claim 16, wherein said detector includes a tubular housing. 18. Apparatus according to any one of claims 13 to 17, wherein said detecting means comprises a semiconductor optical emitter. 19. A method of detecting the content of an impurity in a stream of air, substantially as hereinbefore described with reference to the accompanying drawings. 20. Apparatus for detecting the content of an impurity in a stream of air, substantially as hereinbefore described with reference to the accompanying drawings." 8 The Commissioner took the view that an appeal having been lodged against the delegate's decision made on 2 March 2005, the whole matter of the applicant's entitlement to a patent was before the Court and that the delegate should take no further action under Chapter 5 of the Act. That approach meant that Airsense Technology was in a position where the terms of the claims by reference to which it had filed its appeal differed from those which existed on the Commissioner's file, and yet the Commissioner herself declined to proceed further with the claims on her file. In those circumstances, Airsense Technology applied by a notice of motion in its appeal for a direction that: "… the trial and determination of the appeal in this proceeding and all evidence in this appeal be directed to the patent application with the form of the specification as amended." 9 The notice of motion came on for hearing before Jessup J. On 31 May 2007, his Honour decided that the notice of motion should be dismissed. In the course of his reasons (Airsense Technology Ltd v Vision Systems Ltd (2007) FCA 828; (2007) 73 IPR 65) his Honour said (73 IPR 72-73 [15]-[16]): "Although New England Biolabs was directly concerned with an appeal under s 104(7) of the Act, their Honours on the Full Court discussed the content and history of relevant provisions of the Act in terms which make it clear that, under s 60(4) no less than under s 104(7), the subject matter of the appeal is the same subject matter as was before the original decision maker. Their conclusion in that regard expressly took account of the different kinds of powers exercised by each (first executive, then judicial) and of the nature of such an appeal (by way of hearing de novo). It follows that, under s 60(4), an appeal is limited to the subject matter which was before the delegate under s 60(1). In the present case, I consider that the effect of granting the applicant's motion would involve a change of subject matter, and would introduce claims in relation to which the proceeding could not be considered to be an 'appeal' in the sense explained in New England Biolabs. For the foregoing reasons I propose to dismiss the motion. As will be clear, I do so because of my understanding of the nature of an appeal under s 60(4) of the Act, and not in the exercise of a discretion. However, I would add that, had some discretionary element been involved in the decision I am required to make, I would have been disposed to accept the broad thrust of the respondent's case that it would be antithetical to the achievement of the objects of Ch 5 of the Act that appellate proceedings under s 60(4) should be used as the vehicle for the primary testing of substantive claims against such legitimate grounds of opposition as there may be, without those claims first having been dealt with by the commissioner or her delegate. The significance of that consideration is in no sense diminished by the undoubted fact that an appeal must proceed as a hearing de novo. Even in such a case, I would have considerable reservations about an approach which had the practical effect of collapsing the distinction, well-recognised in the Act, between the role of the primary decision maker and the appellate role of the court. It is not for me to opine that that is a useful distinction: the fact is that it is one which has been made by the legislation, and must be respected. Neither should I assume, in the present case, that the resumed hearing before the delegate under s 60(1) of the Act would be tokenistic. To the contrary, I am bound to treat such a hearing as the primary means established by the legislation for resolving such grounds of opposition as are raised." 10 On 10 December 2008, a delegate of the Commissioner decided that Patent application No 689484 (which by that time was in the name of Aspirating IP Limited), together with each and every one of claims 1 to 20 should be refused. The delegate decided that, despite the amendments to the claims, the fact that claims 1 and 3 were in the same form as they were when they were before the delegate who made the decision on 2 March 2005, meant that the Patent application had to be refused. The delegate said that the parties had agreed that it was not necessary to consider whether there were any objections to the remaining claims, namely, claims 2 and 4-20 inclusive. 11 Aspirating IP Limited ("Aspirating IP") appealed to this Court against the delegate's decision made on 10 December 2008 (VID 1042 of 2008) and in that appeal it sought orders that the delegate's decision made on 10 December 2008 be quashed or set aside, that the appeal be allowed, that the opposition be dismissed and that the opposed application as amended be ordered to proceed to grant. 12 It is fair to say neither delegate considered a number of the claims which are part of the set of 20 claims. Furthermore, there is evidence before the Court on novelty, inventive step and entitlement which was not before either delegate. Those matters are identified in a document prepared by the respondent and entitled "Evidence before the Court that was not before the Patent Office". 13 Pursuant to orders made by Jessup J on 19 February 2009 the respondent, Vision Systems, filed a Statement of Grounds of Invalidity, and Particulars of the Statement of Grounds of Invalidity. On the same day his Honour made orders in both proceedings that: "(1) the evidence in the proceedings before the Commissioner be evidence in these proceedings, saving all just exceptions; and (2) that evidence in proceeding SAD 59 of 2005 be taken to have been filed and served in proceeding VID 1042 of 2008." 14 The parties are agreed that the claim set of 20 claims as allowed by the Commissioner of Patents on 26 September 2006 should be that considered by the Court as the opposed claims and that the Court's decision in relation to those 20 claims will determine both appeals. 15 The broad issues on the appeals and cross appeal are identified in the respondent's Statement of Grounds of Invalidity and Third Further Amended Particulars of Statement of Grounds of Invalidity dated 27 March 2009 in proceeding VID 1042 of 2008. The latter document was filed in Court on 29 October 2009. The broad issues are as follows: 1. The Applicant is not entitled, or solely entitled, to the grant of a patent for the invention. 2. The alleged invention is not a patentable invention in that, when compared with the prior art base as it existed before the priority date of each claim, none of the claims: (1) is novel; (2) involves an inventive step. 16 In relation to the challenge on the ground of lack of novelty the respondent relies on prior publications and prior uses. It relies on 12 publications before 30 July 1993 and three publications between 30 July 1993 and 1 August 1994. The significance of these two dates is that the applicant contends that the priority date is 30 July 1993, whereas the respondent contends that the priority date is 1 August 1994. For reasons I will give, I hold that the priority date is 30 July 1993 and it follows that the three publications after that date are not relevant in terms of the challenge on the ground of lack of novelty. The respondent also relies on six prior uses or types of prior use to defeat novelty. All of these are said to have taken place before 30 July 1993. 17 In relation to the inventive step challenge, the respondent relies on common general knowledge which it pleads comprised 59 publications and in excess of 10 prior uses or types of prior use. In the alternative, it relies on common general knowledge and, pursuant to s 7(3) of the Act, one of the items of listed prior publications or prior uses. 18 This is a brief summary of the pleadings at the time of trial. As the trial proceeded the issues between the parties narrowed and a number of arguments raised by each party, and the subject of evidence, were abandoned.

The Hearing of the Appeals 19 The nature of an appeal under s 60(4) of the Act is well established. It is not an appeal in the strict sense, but is a proceeding in the original jurisdiction of the Court and is conducted as a rehearing. It is sometimes referred to as a hearing de novo (see generally the principles identified by the Full Court of this Court in Commissioner of Patents v Sherman (2008) 172 FCR 394 ("Commissioner of Patents v Sherman") at 399-401 [18]-[24]. 20 A number of witnesses gave evidence before me and many exhibits (including affidavits of deponents not required for cross-examination) were admitted in evidence. The respondent called Dr Martin Cole, Mr Hans Verzijl, Mr Kjell Jawerth, Mr Raymond Walsh, Mr Frank Trubshaw, Mr Michael John Scully, Mr Peter Johnson, Mr Harold Piik-Wakeling, Mr Jonathon Miles, Mr John Petersen and Mr Ronald Knox. The applicant called Mr Fox, Mr David Barrett, Mr David Mitchell, Mr Howard Bray, Mr Anthony Jennings and Mr Julian Whitta. 21 The respondent presented its case first and its first witness was Dr Cole. 22 There was a strong challenge by the applicant to Dr Cole's credit, particularly in relation to his evidence of his thoughts about a bypass arrangement in 1992 or 1993 and his evidence of the smoke detection system at the European Centre for Nuclear Research ("CERN"). I consider those challenges below. In the result, I have reached the conclusion that Dr Cole was an honest and reliable witness. Furthermore, he is highly qualified in the area of fluid dynamics and the design and operation of smoke detection systems. 23 There was also a strong challenge by the applicant to Mr Miles' evidence. That challenge is dealt with below. In the result, and for the reasons I will give, I have decided not to act on Mr Miles' evidence on certain key issues. 24 For the most part the applicant did not challenge the credit of the other witnesses called by the respondent. It certainly suggested that aspects of evidence of those witnesses was unreliable or should not be accepted for various reasons. It made a strong attack on the inventive step evidence of Messrs Jawerth, Johnson and Piik-Wakeling. I will deal with the particular challenges in the context of the issue to which the evidence was directed. 25 Mr Fox was the first witness called by the applicant. Twenty-two affidavits sworn by Mr Fox were tendered in evidence and he was cross-examined at length. 26 Mr Fox holds an 85 per cent interest in the applicant. He has a significant financial interest in the outcome of these proceedings. He believes that Xtralis has sold a product which falls within the claims of the Patent application and that if the Patent proceeds to grant he will be entitled to a very significant sum of money. 27 It seems that there was a close friendship between Mr Fox and Dr Cole before the former's dismissal from his employment by IEI (UK). It seems that Dr Cole made serious allegations of misconduct against Mr Fox at the time of dismissal and that led to a complete breakdown in their friendship. For some time after October 1992 Mr Fox had an intense personal dislike of Dr Cole. 28 Mr Fox has spent his working life in the United Kingdom. Before and after the priority date he has worked in the fire and smoke detection industry. He has a knowledge of smoke detectors and how they work, although he is not a technician in the sense that Mr Girling was when Mr Girling worked for IEI (UK) and Airsense Technology. Mr Fox has no tertiary qualifications in engineering or fluid dynamics. 29 I do not understand Mr Fox to have worked at any time in Australia. However, he had some knowledge of the industry in Australia by reason of the relationship between IEI (Aust) and IEI (UK) and visits to Australia from time to time. His employer before IEI (UK) also had a commercial relationship with an Australian company. It was not always made clear during his evidence when he was purporting to give evidence of common general knowledge of the industry in Australia. 30 In general, I accept Mr Fox's evidence on factual matters and I mean by that his evidence as explained and qualified in cross-examination. For reasons I will give in the section dealing with entitlement, I am not satisfied that he was aware of Mr Scully's prototype. On technical matters such as the Venturi effect, I accept Dr Cole's evidence in preference to that of Mr Fox. In terms of the fire and smoke detection industry in Australia before the priority date I do not think that there was a great deal of difference between Mr Fox's evidence on that topic and the evidence of Dr Cole and Messrs Jawerth, Johnson and Piik-Wakeling. In so far as there were differences, I accept the evidence of the latter group of witnesses because their knowledge was superior to that of Mr Fox. 31 Mr Fox believes strongly that an air-conditioning duct is not a main duct means in the form of sampling duct means of a smoke detection system within the claims. He gave evidence on that topic, various pieces of prior art, inventive step and the Brown, Moores and Birkby article. As with the other witnesses who gave evidence on those topics I have carefully considered Mr Fox's evidence. Ultimately, however, the questions raised are questions which I must determine. 32 The respondent did not mount an attack on the credit of any of the applicant's other witnesses. Certainly it asked me to reject aspects of the evidence of each of the witnesses, but it did so on the basis that the witness lacked expertise or had made an appropriate concession in cross-examination or the evidence, when closely analysed, was no more than argument.

The Onus on the Respondent 33 It is well established that an opposition will be upheld only where it is practically certain that the patent, if granted, would be invalid (Commissioner of Patents v Microcell Ltd (1958) 102 CLR 232 at 244-245; Genetics Institute Inc v Kirin-Amgen Inc (1999) 92 FCR 106 at 112 [17]). Other formulations of the relevant test have been used, but they are to similar effect: Austal Ships v Stena Rederi Aktiebolag (2005) 66 IPR 420 ("Austal Ships") at 422 [6] per Bennett J and Commissioner of Patents v Sherman at 399 [18] "clearly satisfied"; F Hoffman-La Roche AG v New Zealand Biolabs Inc ("F Hoffman-La Roche AG") (2000) 99 FCR 56 at 70 [67] per Emmett J "appear clear to the Court"; Farbwerke Hoechst Aktiengesellschaft Vormals Meister Lucius & Bruning v Commissioner of Patents (1971) 124 CLR 654 at 664 per Gibbs J (as he then was) "unless it clearly appears". 34 The respondent accepts that the relevant test is one of practical certainty. It does not suggest that, because a large volume of evidence has been put before the Court and there has been extensive cross-examination of witnesses, a lower or less demanding test should be applied. Such a submission would have encountered difficulties in light of the authorities (for example, Austal Ships at 423 [9] per Bennett J; F Hoffman-La Roche AG at 70 [67] per Emmett J). 35 The primary facts are to be established on the balance of probabilities, but the ultimate facts - the facts leading directly to a conclusion of a lack of novelty or a conclusion of obviousness - must be proved to the level of practical certainty. In Austal Ships, Bennett J said (at 423 [12]): "I can accept that a lower standard may apply to proof of evidence such as whether a document has been published or, indeed, whether a prior art vessel was well-known. I do not accept that it properly applies to the factual question that itself is the test for obviousness or lack of inventive step. Where the factual question is itself the legal test, as set out in s 7(3) of the Act, it seems to me that it should be determined at the higher standard. That means that where there are two opposing expert views that are conclusive on obviousness, both presented bona fide by witnesses of accepted expertise, unless one set of views can be rejected on proper grounds, the legal burden to establish a ground of opposition is not discharged; the court cannot be practically certain that obviousness or lack of inventive step is established."

The Parties 36 The respondent admits, for the purposes of these proceedings, that Aspirating IP Limited holds the rights previously held by Airsense Technology. 37 Mr Peter Fox began his working life in the smoke detection industry in the early 1970s. He undertook an apprenticeship in mechanical engineering with Graviner Limited, an English company which was a market leader in aircraft fire detection. In 1977, Mr Fox joined the then family business of Fire Fighting Enterprises (UK) Ltd ("FFE-UK"). That company was a partially owned subsidiary of Fire Fighting Enterprises Australia Ltd. The company was primarily involved in the development of gaseous fire extinguishers and automatic fire detection and suppression systems. FFE-UK also developed and manufactured a range of smoke detection devices at its premises in Stevenage, Hertfordshire, United Kingdom. The designer of those detectors was Mr Christopher Girling who later became engineering manager of IEI (UK) and later still a partner in Airsense Technology. 38 In late 1987 or early 1988, Mr Fox was approached by Dr Martin Cole (then Mr Cole), who proposed to Mr Fox that a new company be formed and that that company be a partially owned subsidiary of IEI (Aust). IEI (UK) was formed, and Mr Fox held 40 per cent of the shares in the company. Mr Fox became the managing director of the company. 39 In October 1992 Dr Cole dismissed Mr Fox from his employment by IEI (UK). The reasons for the dismissal of Mr Fox are not an issue in the proceedings and, although there was some evidence on the topic, it is not necessary for me to make any findings with respect to the topic. It appears that one of the matters leading up to Mr Fox's dismissal was a disagreement between Mr Fox and Dr Cole about whether a smoke detection system called the E7 AZ PYR should be offered on a large project known as the Glaxo project. This particular issue is dealt with in more detail below in the context of the issue of entitlement. 40 Mr Fox brought a claim for unfair dismissal against IEI (UK). That claim was eventually settled without the need for a trial. Mr Fox spent a good deal of time preparing his claim for unfair dismissal in the latter part of 1992 and the early part of 1993. 41 For some time prior to July 1993 Mr Fox was aware of a problem with the filters used in the smoke detection systems sold by IEI (UK). The problem was that over time the filter became clogged and that prevented the particles to be detected, that is, smoke particles, from reaching the detector. The problem came to a head in 1992 when the "Spanish problem" arose. Further details of the "Spanish problem" are set out below (at [362]) 42 Mr Girling resigned from his employment by IEI (UK) in about February 1993. At about that time, Mr Fox and Mr Girling decided to incorporate a company to engage in the business of designing and marketing products in the smoke detection industry. The company which was acquired for that purpose was Airsense Technology. 43 Mr Fox assembled a team of engineers to work under Mr Girling. A smoke detection system was designed and it became known as the "Stratos-HSSD" system. 44 The Stratos-HSSD system contained several new features. Mr Fox developed the idea of a bypass system which he described as a system "so that only a small proportion of the air in the smoke detection system flowed for detection through the filter and detector, rather than the whole stream of air as in the then existing VESDA systems". 45 In August 1993, Airsense Technology supplied a single Stratos-HSSD detector to a fire protection company in the United Kingdom called Fire Detection and Extinguishing Systems Limited. 46 The bypass arrangement is at the heart of the alleged invention. It is embodied in the Stratos-HSSD system. Mr Fox said that many thousands of Stratos-HSSD systems have been sold worldwide and that it has been commercially successful for Airsense Technology. In 1999, Airsense Technology received a Queen's Award for Technological Achievement for the technological advances embodied in the Stratos-HSSD system. 47 Mr Girling died in 2002. Prior to his death he had sworn a number of affidavits. Those affidavits were admitted in evidence at the trial. I have taken them into account, noting at the same time that there was no cross-examination on them. 48 I turn now to the respondent. It acquired IEI (Aust) in about 1995. In more recent times (the precise date was not identified in the evidence) the section of the respondent which manufactured the Very Early Smoke Detection Apparatus smoke detection system ("VESDA") and the "security side" (as Mr Knox put it) was sold to a private equity company called PEP which subsequently changed its name to Xtralis. 49 IEI Pty Ltd was established by Dr Martin Cole in 1970. The company later changed its name to IEI (Aust). It is convenient if I refer to it as if its name has always been IEI (Aust). Dr Cole was the chief executive officer of IEI (Aust). The principal business of IEI (Aust) was the manufacture and sale of smoke detectors. Although Dr Cole was the chief executive officer, he also had a close involvement in the design, manufacturing and marketing of the smoke detectors made and sold by IEI (Aust). At the priority date of 30 July 1993 and it seems, for some time both before and after that date, IEI (Aust) was a major manufacturer and supplier of smoke detectors in Australia. 50 A successful product manufactured and sold by IEI (Aust) was a smoke detection system called a VESDA E700. Various models of the VESDA E700 were manufactured and sold by IEI (Aust) and they were referred to as the Mk I, Mk II and Mk III. IEI (Aust) considered that the VESDA E700 Mk II was an advance on the Mk I in terms of the features it offered and that the Mk III was an advance on the Mk II. The VESDA Mk I was first sold in the market in 1979, the Mk II in about 1982 and the Mk III in 1993. In some parts of these reasons it will be necessary for me to refer to the particular model of the VESDA on other occasions it will be sufficient for me to refer to all three models as simply the VESDA E700 units. 51 Other smoke detection systems manufactured and sold by IEI (Aust) or IEI (UK) were the subject of evidence and they include the Locator and the VESDA LaserPlus. When appropriate, I will describe the features of those systems to the extent that the evidence permits me to do so. 52 Other smoke detection systems were manufactured and sold by other companies. Of importance in this case is a smoke detection system sold by Wormald International (Aust) Pty Ltd ("Wormald (Aust)") called an Olsen D51B. I will describe the features of this system later in these reasons. It appears that part of the business of Wormald (Aust) was taken over by Tyco International Ltd in August 1990. 53 Dr Cole has substantial expertise in the area of fluid dynamics and the design and operation of smoke detection systems. In 1972 he was awarded a Diploma of Electronic Engineering by the Royal Melbourne Institute of Technology. In 1991 he was awarded a Master of Engineering degree by Monash University. The topic of his thesis for that degree was "Optimisation of Aspiration Techniques for Air Pollution Monitoring". He then undertook further research and study and was awarded a PhD in fluid dynamics by the Victoria University of Technology. He has spent a good part of his working life working in the area of fluid dynamics and the design and operation of smoke detection systems. 54 For some years after the sale of IEI (Aust) to the respondent Dr Cole continued to work for the respondent. In about 1999 he ceased to have any involvement with the respondent and he established his own business, Cole Innovation and Technology Pty Ltd. 55 Dr Cole is and has been named as the inventor in a number of patents and patent applications. I mention that because I think Dr Cole was an inventive skilled worker in the field of fire or smoke detection systems. 56 When IEI (UK) was established in 1988, IEI (Aust) was the majority shareholder of the company. In 1991 and 1992 Dr Cole, as the chief executive officer of IEI (Aust), had regular contact with employees of IEI (UK). He was regularly consulted and he became involved in major projects in which IEI (UK) was involved, or in which it sought to be involved. During those years IEI (UK)'s premises were at Stevenage, Mr Fox was the managing director of the company and Mr Michael Scully was the technical manager, Mr Christopher Girling was the design engineer and Mr Frank Trubshaw was the sales manager.

Smoke Detectors in Australia Before July 1993 57 There was general evidence before me about the fire or smoke detection industry in Australia before July 1993 which was not in dispute. It is convenient to recount that evidence at this point. 58 The products of fire are gas, particulate smoke, heat and flames. A smoke detector detects airborne products of combustion and is to be distinguished from a heat detector or a flame detector. 59 Smoke detectors operate by reference to one of the following three principles: ionisation, photoelectric obscuration and photoelectric light scattering. This case is not concerned with smoke detectors which operate by a process of ionisation. 60 Photo-electric smoke detectors have a light source and photosensitive cell. The cell operates so as to detect a decrease in the intensity of light received by it in the event that aerosols are between the cell and the light (obscuration) or a reflection of light by the aerosols (light scattering). 61 Prior to July 1993, the main type of smoke detectors were standard "point type" detectors and incipient very high sensitivity detectors. 62 Point type detectors were commonly used in domestic and industrial environments. Such detectors passively sampled air as it was circulated around a room or other protected area. Point type detectors were only able to protect a small volume of air and were relatively less sensitive because they were only triggered when smoke levels were high. A fire could be fairly well developed before the alarm signal was triggered. 63 Incipient detectors detect incipient smoke; they are capable of detecting smaller airborne products which are produced before flaming. Incipient smoke detectors are typically aspirated in that the air is drawn in from the area to be protected and delivered to a remotely positioned smoke detector. Incipient smoke detectors are triggered much earlier than point type detectors.

The VESDA Smoke Detection System 64 Mr John Petersen is the executive director of a company which carries out business in Western Australia. He started his working life in the early 1960s as an electrical apprentice and between 1981 and 1985 he worked for IEI (Aust). He was called as a witness by the respondent. He was a credible and reliable witness and I accept his evidence. Based on his evidence, I provide the following overview of the development of the VESDA smoke detection system and of the products sold by IEI (Aust). 65 In the 1960s the Postmaster General's Department and Commonwealth Scientific and Industrial Research Organisation ("CSIRO") Department of Atmospheric Research worked on the research and development of a smoke detection product which was capable of detecting the smoke from the very early stage of the development of a fire, that is to say, the early stage of combustion. A number of prototypes were built and given the name VESDA. This name was registered jointly by the PMG and the CSIRO. 66 At some stage the further development and manufacture of the VESDA smoke detection system was transferred to IEI (Aust). 67 By 1979 IEI (Aust) was manufacturing and selling the VESDA E700 Mk I. That system had three main applications: commercial and industrial premises, residential premises and stand alone valuable assets such as computer units. 68 It was necessary for the system to draw a sample of air from a protected area. The three ways in which that might be done were as follows: 1. installing the system on a pre-existing air conditioning duct and drawing a sample of the air passing through that duct through the detection unit; 2. installing the system on a dedicated network of sampling pipes and drawing either the whole or a sub-sample of the air passing through that network of pipes through the detection unit; or 3. installing the system with a single sampling pipe, connected to a confined space, such as a computer cubicle, and drawing a sample of air from that confined space through a detection unit. 69 The VESDA E700 Mk I consisted of a tube with two box type structures attached to it. The tube contained an optical sensing chamber. One box contained a Xenon light source which flashed across the chamber thereby illuminating any airborne particles present, which in turn scattered light into the path of the sensing device. The other box contained a photomultiplier sensing device which detected the light scattered off particles that may be present in the optical chamber at the time of each flash of the Xenon light. There was also a display and control panel. The VESDA E700 Mk I could be attached to an air-conditioning duct where it drew and expelled air through two small tubes attached to the duct; to a dedicated network of sampling pipes consisting of branch pipes, a trunk pipe and an outlet fan; or to a single sampling pipe in a confined space such as a computer cubicle. 70 As I have said, IEI (Aust) manufactured and sold the VESDA E700 Mk II from about 1982. The advances over the Mk I were in part prompted by IEI (Aust)'s major customers (which for the most part were fire protection companies) asking IEI (Aust) to supply all the major components of a complete system. For example, a fan should come with the system rather than having to be purchased separately. At about this time, Dr Cole was considering the inclusion of a filter with the unit. This would allow the passage of smoke particles, but filter out the passage of unwanted contaminants such as dust. 71 When first sold in the market the components of the E700 Mk II were in a metal box and included an aspirator. A short time after it was introduced a filter was included in the VESDA E700 Mk II. The filter was a folded paper cartridge type, similar to oil filters used in the automotive industry and it was placed upstream (that is, before) of the detection unit.

A Description of the Claims 72 I refer to the 20 claims set out in [7] above. 73 The respondent provided a convenient summary of the features of each of the claims. It is as follows: Claims 1 and 3 are independent claims which have the following features: · a method of, or apparatus for, detecting the content of an impurity in a stream of air; · the stream of air which contains the impurity flows through a main duct means in the form of a sampling duct means of a smoke detection system; · a secondary duct means which communicates with the main duct means; · part only of the stream of air flows from the main duct means into the secondary duct means; · a particles filter is disposed in the secondary duct means to filter the air in the secondary duct means; and · an impurity detector in the secondary duct means and downstream of the particles filter which is used to detect the impurity in the air in the secondary duct means. Claims 2 (a dependent claim) and 13 (an independent claim) have the following features: · the main duct passes through a detection module; and · the detection module contains said secondary duct means, said filter and said detecting means. Claims 4 and 6 are independent claims which have the following features: · the impurity that is to be detected is a particulate impurity; and · the particles filter in the secondary duct means removes particles larger than those intended to be detected from the said air stream. Claims 5 and 7 are dependent claims and have the following feature, namely, the addition of the detection module feature to claims 4 and 6. Claims 8 and 14 are dependent claims which have the following feature, namely, a mechanical powered means (for forcing air to flow through the main duct means, the secondary duct means, the particles filter and the detector) is located in the main duct means and upstream of the secondary duct means. Claims 9 and 15 are dependent claims which have the feature that the sampling duct means includes a plurality of sampling pipes. Claims 10 and 16 are dependent claims which have the feature that the detecting means is a single detector. Claims 11 and 17 are dependent claims which have the feature that the detector has a tubular housing. Claims 12 and 18 are dependent claims which have the feature that the detecting means or detector comprises a semiconductor optical emitter. Claims 19 and 20 are omnibus claims being the method and apparatus for detecting the content of an impurity in a stream of air, substantially as described in the specification.

THE Priority date of each claim 74 The Australian complete application No 689484 is entitled to an earlier priority date than would otherwise be the case if it was made pursuant to the Patent Cooperation Treaty and ss 88-93 of the Act. The complete application was based on an application under the Patent Cooperation Treaty ([1980] ATS 6) filed in the United Kingdom on 1 August 1994. That application was in turn based on the British Patent Application No GB 931 5779 filed on 30 July 1993. The Australian complete application No 689484 claims a priority date of 30 July 1993 based on the British Patent Application No GB 931 5779 as the Basic Application. I will refer to the latter as the UK Basic. 75 The respondent disputes the applicant's entitlement to a priority date of 30 July 1993. It contends that the priority date is 1 August 1994. In the alternative, the respondent submits that the priority date of claims 2, 5, 7, and 13 (and their dependent claims) and claims 8 and 14 is 1 August 1994. 76 The priority date is important in this case because the respondent alleges that there was prior art information which was made publicly available between 30 July 1993 and 1 August 1994 and that this means the alleged invention lacks novelty. That prior art information consists of an article by Mr Fox and Mr Girling entitled "A New Generation of High Sensitivity Smoke Detectors", published in a journal or magazine called Fire Surveyor, (August 1993, pp 22-29) and the technical manual for the Stratos-HSSD published in or about April 1994 by Airsense Technology. Those publications were said by the respondent to anticipate a number of the claims in the specification of the Patent application. 77 The priority date of a specification is dealt with in s 43 of the Act which, at the relevant time, was in the following terms: "43 Priority dates

(1) Each claim of a specification must have a priority date. (2) The priority date of a claim is: (a) the date of filing of the specification; or (b) where the regulations provide for the determination of a different date as the priority date - the date determined under the regulations. (3) Where a claim defines more than one form of an invention, then, for the purposes of determining the priority date of the claim, it must be treated as if it were a separate claim for each form of the invention that is defined. (4) The priority date of a claim of a specification may be different from the priority date of any other claim of the specification." 78 There were regulations which provided for the determination of a different date as the priority date. Regulation 3.12 was in the following terms, relevantly: "(1) Subject to regulations 3.13 ('priority dates: certain persons and applications') and 3.14 ('priority dates: certain amended claims') and subregulation (2), the priority date of a claim of a specification is the earliest of the following dates: (a) the date of filing of the specification; (b) if the claim is fairly based on matter disclosed in 1 or more relevant applications, the date of making the relevant application in which the matter was disclosed; … (2) In paragraph (1)(b), 'relevant application' means" … (c) if the application is a PCT application that claims priority under Article 8 of the PCT of an earlier application that is: … (ii) a basic application that is: (A) the first application made in a Convention country in respect of the invention; and (B) made not more than 12 months before the international filing date of the PCT application; or (iii) a basic application made after a basic application referred to in subparagraph (ii); that earlier application; or…" 79 The applicant claims that the priority date is 30 July 1993 because the claims are fairly based on the UK Basic. 80 Each party made a submission that the other party bore the onus of proof on the question of the priority date; the applicant claimed that the respondent must negate the earlier priority date and the respondent claimed that the applicant must prove the earlier priority date. 81 I have already referred to the onus which lies on an opponent in opposition proceedings. For its part, the respondent referred to English authority which suggested that the onus was on the applicant for a patent to prove an earlier date of priority than the date of the filing of the specification: Re Stauffer Chemical Company's Application [1977] RPC 33 ("Re Stauffer")at 54 per Buckley LJ; 54-55 per Roskill LJ. There is certainly dicta in the reasons for judgment of Roskill LJ which supports the respondent's contention. 82 The applicant referred to Sigma Pharmaceuticals (Australia) Pty Ltd (ACN 004 118 594) v Wyeth (2009) 81 IPR 339 ("Sigma Pharmaceuticals"), a case in which Sundberg J said that an applicant for a patent did not bear any onus in relation to the priority date. His Honour said (at 344 [21]): "Establishing a priority date other than that claimed by the patentee is part of Sigma's attack on validity." 83 It does not seem to me that there is anything in the text or structure of s 43 of the Act which supports the respondent's contention that the onus is on the applicant for a patent to prove an earlier priority date. One date is identified by reference to a criterion in the Act, whereas the other is identified by reference to a criterion in the Regulations. It may be that one date may be more easily ascertained than the other, but even so, the date identified in reg 3.12(1)(b) is determined by an examination of documents. There does not seem to me to be anything to suggest that the general onus on an opponent in opposition proceedings should be shifted to the applicant on the issue of the priority date. I would be disposed to follow the approach of Sundberg J in Sigma Pharmaceuticals. I should add that I have been able to decide this issue without relying on the onus of proof.

Relevant principles 84 The legal principles relevant to fair basing are not in dispute. Questions of fair basing may arise in a number of contexts. For example, there is the present context and there is internal fair basing referred to in s 40(3) of the Act. The test appears to be the same in both contexts (see the discussion in Stewart A, Griffith P and Bannister J, Intellectual Property in Australia (4th ed, 2010) at 424). 85 In Société Des Usines Chimiques Rhône-Poulenc v Commissioner of Patents (1959) 100 CLR 5 at 11, Fullagar J said that fair basing required "a real and reasonably clear disclosure". In Olin Corporation v Super Cartridge Co Pty Ltd (1977) 180 CLR 236 at 240, Barwick CJ said that the question of whether the claim was fairly based was a narrow one and was whether the claim as expressed travelled beyond the matter disclosed in the specification. Both these ways of expressing the test were approved by the High Court in Lockwood Security Products Pty Ltd v Doric Products Pty Ltd (2004) 217 CLR 274 at 295-296 [57]; at 300 [69]; and 306 [83], which was an internal fair basing case. The High Court also made the point that the fact that something is a requirement for the best method of performing an invention does not make it a requirement of all claims; nor does the fact that material is part of the description of the invention mean that it must be included as an integer of each claim. The Court cited with approval (at 300 [69]) the following passage from the reasons for judgment of Gummow J in Rehm Pty Ltd v Websters Security Systems (International) Pty Ltd (1988) 81 ALR 79 where his Honour said (at 95): "The circumstance that something is a requirement for the best method of performing an invention does not make it necessarily a requirement for all claims; likewise, the circumstance that material is part of the description of the invention does not mean that it must be included as an integer of each claim. Rather, the question is whether there is a real and reasonably clear disclosure in the body of the specification of what is then claimed, so that the alleged invention as claimed is broadly, that is to say in a general sense, described in the body of the specification." 86 In CCOM Pty Ltd v Jiejing Pty Ltd (1994) 51 FCR 260 the Full Court made the following important observations (at 281-282): "In Rhone-Poulenc (supra) at 11 Fullagar J emphasised that disclosure without claim is enough. Hence, it is wrong to proceed as if testing for infringement and to seek to isolate in the body of the complete specification, or in the provisional specification, 'essential integers' or 'essential features' of an invention disclosed therein and to ask whether they correspond with the essential integers in the claim in question: cf Coopers Animal Health Australia Ltd v Western Stock Distributors Pty Ltd (1986) 6 IPR 545 at 560-561, the decision at first instance. Nor would it be applying the statute to ask whether the earlier specifications fairly described the essential features of the invention disclosed in the later specification: cf Yamazaki (supra) at 93, 97. Fullagar J also pointed out that the requirement of 'fair basing' on matter disclosed in an earlier specification would be senseless if what was required was that the subject matter of the claim must have been actually claimed in the earlier specification; rather, there must be 'a real and reasonably clear disclosure'. This passage was adopted and applied by Gibbs J in Hoffman-La Roche at 537-539, where the claims were for chemical compounds forming part of a very large class disclosed in the basic application." (See also the summary of the relevant principles by Dowsett J in Grove Hill Pty Ltd v Great Western Corporation Pty Ltd (2002) 55 IPR 257 at 306-308 [187]-[190].) 87 Finally, mention must be made of the English authority of Re Stauffer which I have already referred to in the context of the issue as to which party bears the onus of proving the priority date. Buckley LJ said the following as to fair basing (at 54): "Can these new features be regarded as developments or additions the introduction of which is justified by section 4(6)? If a new feature were a development along the same line of thought which constitutes or underlies the invention described in the earlier document, it might be that that development could properly be regarded as fairly based on the matter disclosed in the earlier document, and that the new process described in the later document which incorporates that development could as a whole be regarded as fairly based upon the matter disclosed in the earlier document. If, on the other hand, the additional feature involves a new inventive step or brings something new into the combination which represents a departure from the idea of the invention described in the earlier document, it could not, I think, be properly described as fairly based upon the earlier document." 88 I turn now to apply these principles to the facts.

The issues concerning the priority date in relation to each claim 89 The respondent made three broad submissions. First, it submitted that the priority date for all claims was 1 August 1994. Secondly, it submitted that the claims referring to mechanical powered means (claims 8 and 14) had a priority date of 1 August 1994. Finally, it submitted that the claims referring to a detection module (claims 2, 5, 7 and 13) had a priority date of 1 August 1994.

A secondary duct means communicating with a main duct means 90 The respondent submits that all of the claims in the specification of the Patent application have a priority date of 1 August 1994 because in referring to a "secondary duct means" and a secondary duct means "communicating with" a main duct means, the claims in the specification travel beyond any matter disclosed in the UK Basic. The respondent refers to the fact that in Figure 2 of the specification of the patent application the secondary duct means is shown as being inside the main duct means in what was described as a co-axial arrangement. Under the claims in the specification the secondary duct means can join the main duct means or it can be inside the main duct means as shown in Figure 2. 91 By contrast (submits the respondent) the UK Basic refers only to branch duct means and that has the meaning and only the meaning of a duct which joins the main duct means. 92 The UK Basic identifies the problem the invention is designed to address in the following way: "In order to prevent the internal parts of a transducer from becoming contaminated, an air filter is employed to remove larger particles than anticipated with products of overheating materials. The performance and renewal of this filter, with known aspirating detectors, is often a problem in maintaining a consistent performance by a detector. The problem arises in that, as the air filter becomes increasingly contaminated through usage, the effective pore size of filter medium becomes increasingly smaller. This effect is sometimes known as 'tea leafing' because of the similarity with the effect of tea leaves hindering passage of tea when a tea strainer is used. The effect on conventional aspirating smoke detectors is that the sensitivity of the detector decays with time as the filter becomes increasingly blocked, leaving the system in some cases significantly less sensitive after only a few months of use.

Furthermore, in existing aspirating smoke detection systems, it is desirable that the rate of air flow down the sampling pipes is at a maximum, because this minimises response time to fire situations. By reason of the high rate of flow down the sampling pipes, it is also likely that significant amounts of pollution other than smoke and having the aforementioned tendency to block filters will be drawn into the detector." In addressing the aspects of the invention, the UK Basic provides: "According to a sixth aspect of the present invention, there is provided a method of detecting the content of impurity in a stream of gaseous medium flowing through main duct means, comprising causing part of said stream to branch out into branch duct means and detecting the content of the impurity in the gaseous medium in said branch duct means.

According to a seventh aspect of the present invention, there is provided apparatus for detecting the content of impurity in a stream of gaseous medium, comprising main duct means through which said stream can flow, branch duct means branching from said main duct means for receiving part of said stream, and detecting means serving to detect the content of the impurity in the gaseous medium in said branch duct means.

Owing to these two aspects of the present invention, the response time of the detecting means to the content of impurity entering the main duct means need not be dependent upon the throughflow cross-sectional area of a detection chamber and, moreover, the detecting means is not exposed to all of the impurity flowing through the main duct means, whereby the service life of the detecting means may be improved." In describing the apparatus and the "simple bypass arrangement" the UK Basic provides: "The apparatus has a simple bypass arrangement, such that, as the air stream is drawn into an enclosure for the smoke detector, a large proportion of the air is vented to atmosphere or to the air return flow when such a return air passage exists, without entering the filter and thus the detector downstream of the filter. This leaves only a smaller, representative sample of the air to pass through the filter and then the detector. This has the advantages that the maximum rate of flow down the sampling pipes is obtained in order to minimise response time of the detector to a fire situation, and that, as only a small percentage of the potentially contaminating airflow is passed through the filter, the filter and detector service lives are increased." 93 In my opinion, the respondent's submission that the claims in the specification "travel beyond" the UK Basic because the terms "secondary duct means" and "secondary duct means communicating with said main duct means" in the claims in the specification are wider than the "branching out" and "branching from" referred to in the UK Basic must be rejected. The UK Basic was a provisional specification in which a general description was sufficient. Furthermore, the UK Basic must be read as a whole and that includes the passage describing the simple bypass arrangement as set out above. There is nothing in that passage which restricts the disclosure made in the UK Basic to a secondary duct which joins the main duct. I think the UK Basic contains a real and reasonably clear disclosure of a bypass arrangement which includes a second or subsidiary duct which is within a main or major duct, or is joined to a main or major duct.

Mechanical powered means 94 The respondent submits that the priority date for claims 8 and 14 in the specification is 1 August 1994 because each of those claims refers to mechanical powered means located in the main duct means and upstream of the secondary duct means whereas there is no mention of such matters in the UK Basic. 95 The following passage in the UK Basic is relevant to this submission. "The problem of detecting a fire by means of smoke detection is not entirely solved by using a very sensitive aspirating detector." 96 In this context, it is also relevant to note references in the UK Basic to conventional aspirating smoke detectors (see the first passage in [92] above) and to air being drawn into an enclosure (see the third passage in [92] above). 97 I think that the real thrust of the respondent's submission is that there was nothing in the UK Basic to indicate whether the powered means was to be located upstream or downstream of the secondary duct. The respondent submits that, if anything, the UK Basic teaches that the powered means is to be located downstream of the detector because it refers to air being drawn into an enclosure. 98 I reject the respondent's second submission. There are clearly references in the UK Basic to the smoke detection system being an aspirating smoke detection system and, in my opinion, that disclosure is wide enough to include powered means located either upstream or downstream of secondary duct means. If anything, claims 8 and 14 operate to narrow the matter disclosed in the UK Basic.

Detection module 99 The respondent submits that the priority date for claims 2, 5, 7 and 13 in the specification is 1 August 1994 because each of those claims refers to a detection module through which the main duct means extends and which contains the secondary duct means, the filter and the detecting means whereas there is no mention of a detection module of this nature in the UK Basic. The UK Basic refers to "existing aspirating smoke detection systems", "air pollution detection unit[s]", a detector comprising "a housing", an "apparatus", the detector including a "tubular housing" and the air stream being drawn into "an enclosure for the smoke detector". The respondent submits that, although there is a reference to an enclosure for the smoke detector, there is no reference to a detection module. 100 I reject the respondent's third submission. In my opinion, a detection module of the nature described in the claims is a development "along the same line of thought" as that which constitutes or underlies the invention identified in the UK Basic (see Re Stauffer at 54 per Buckley LJ) and therefore may be regarded as fairly based on the UK Basic.

Conclusion 101 In my opinion, the priority date for all the claims in the Specification is 30 July 1993. 102 Before leaving the topic of priority date, in case I am wrong in rejecting the respondent's submission that the priority date is 1 August 1994, I should indicate my view as to whether the claims in the specification had been anticipated by the article in the Fire Surveyor. I do not need to refer to the Stratos Technical manual because counsel for the respondent accepted that of the two, the article in the Fire Surveyor was the more comprehensive. 103 The evidence before me establishes that the relevant volume of the Fire Surveyor was received by the University of New South Wales on 24 November 1993 and it was available to the public shortly after this date. 104 Mr Fox was cross-examined about the article at some length. There is no need for me to go through the details. I am satisfied that the article disclosed all of the features of claims 1, 3, 4, 6, 9, 10, 12, 15, 16 and 18. There was a dispute between the parties as to whether the article also disclosed the features of claims 2, 5, 7 and 13 (and dependent claims) and, in particular, a detection module of the nature described in those claims. Having regard to the diagrams shown in the article, I think that it did do that. Those diagrams show a main duct entering a box and the words of the article refer to a bypass arrangement which means "only a relatively small, representative sample of the air sample entering Stratos is passed through the dust separator and thence into the detector chamber".

The Construction of the Claims in the Specification 105 Before considering novelty and inventive step it is necessary to construe certain words in the claims. 106 The legal principles which are relevant to the task of construction are well established. 107 In Welch Perrin and Company Proprietary Limited v Worrel (1961) 106 CLR 588 ("Welch Perrin") at 610, Dixon CJ, Kitto and Windeyer JJ identified the following principles. First, a specification is not to be read in the abstract; it is to be construed in the light of the common knowledge in the art before the priority date (see also in this regard, Kimberly-Clark Australia Pty Limited v Arico Trading International Pty Limited (2001) 207 CLR 1 ("Kimberly-Clark Australia") at 16 [24]). Secondly, in construing claims in a specification a court is not construing a written instrument operating inter partes, but rather a public instrument the validity of which depends on the instrument defining a monopoly in a way not reasonably capable of being misunderstood (see also Kimberly-Clark Australia at 19 [34]). Thirdly, a specification is made up of several parts and those parts have different functions. It is not legitimate to narrow or expand the boundaries of a monopoly as fixed by the words of a claim by reference to other parts of the specification. Similarly, where the words of a claim are clear they are not to be made obscure by reference to statements in other parts of the specification. 108 One may add to these principles a principle that where terms in a claim are unclear, those terms may be defined or clarified by reference to the body of the specification: Kimberly-Clark Australia at 12 [15]. 109 The construction of claims in a specification is a matter of law and as such is a matter to be determined by the court. However, the court must by evidence be put in the position of a reader skilled in the relevant art at the relevant date: General Tire and Rubber Company v Firestone Tyre and Rubber Company Limited [1972] RPC 457 ("General Tire v Firestone") at 485. 110 A specification will often refer to, and set out the details of, a preferred embodiment or, as the parties in this case called it, a preferred form of the invention. Unless there is express reference to the preferred form in a claim, it is not permissible to read into a claim the features of the preferred form: Rehm Pty Ltd v Websters Security Systems (International) Pty Ltd (1988) 11 IPR 289 at 298-299. 111 In Kinabalu Investments Pty Ltd v Barron and Rawson Pty Ltd [2008] FCAFC 178, the Full Court of this Court provided a helpful summary of a number of relevant principles. The Court's summary was itself based on a statement of the principles by Hely J in Flexible Steel Lacing Co v Beltreco Ltd (2000) 49 IPR 331 at 349-350 [81]. The Full Court said (at [45]): "Other more specific principles of construction collected in Flexible Steel at [81] are: • a specification should be given a purposive construction rather than a purely literal one; • the hypothetical addressee of the specification is the non-inventive person skilled in the art before the priority date; • the words used in a specification are to be given the meaning the hypothetical addressee would attach to them, both in the light of the addressee's own general knowledge and in the light of what is disclosed in the body of the specification; • as a general rule, the terms of the specification should be accorded their ordinary English meaning; • evidence can be given by experts on the meaning those skilled in the art would give to technical or scientific terms and phrases, and on unusual or special meanings given by such persons to words which might otherwise bear their ordinary meaning; • however, the construction of the specification is for the court, not for the expert. In so far as a view expressed by an expert depends upon a reading of the patent, it cannot carry the day unless the court reads the patent in the same way." (See also Sachtler GmbH and Co KG v RE Miller Pty Ltd (2005) 65 IPR 605 at 613 [42] per Bennett J; Insta Image Pty Ltd v KD Kanopy Australia Pty Ltd (2008) 78 IPR 20 ("Insta Image") at 36 [82]; PAC Mining Pty Ltd v Esco Corporation (2009) 80 IPR 1 at 14-15 [29]; Kimberly-Clark Australia at 16 [24].) 112 As I have said, the hypothetical addressee of a patent specification is a person skilled in the art at the priority date. That person is a non-inventive person. The evidence of a person skilled in the art may assist the Court on the meaning to be given to technical terms or terms of art and, more generally, as to the way in which the specification would be read by a person skilled in the art at the priority date. The level of skill of such a person may vary: Jupiters Ltd v Neurizon Pty Ltd (2005) 65 IPR 86 (at 117-118 [154]); Insta Image at 38 [94]-[96]. 113 In this case, the skilled worker is a person who has knowledge of the design, construction or use of fire or smoke detection systems. 114 By reason of the issues in this case, including the composition of the prior art base relied on by the respondent, the words or phrases in the claims which must be construed are the following: · "main duct means in the form of sampling duct means of a smoke detection system" · "particles filter" · "detecting means" · "detection module" 115 The applicant submitted in its closing written submissions that the claims in the specification were limited to high sensitivity aspirating smoke detection systems, but that alleged limitation on the claims was abandoned by counsel for the applicant at the commencement of his oral submissions. 116 The reason that the construction of the phrase "main duct means in the form of sampling duct means of a smoke detection system" is important in this case is that the evidence establishes that in Australia before the priority date the air drawn into smoke detection systems was drawn either from air-conditioning ducts or from a dedicated network of sampling pipes. As is perhaps obvious, as a general rule, pipes forming part of a dedicated network of sampling pipes were used only as part of a smoke detection system. The applicant's contention is that the phrase "main duct means in the form of sampling duct means of a smoke detection system" refers to dedicated sampling pipes and does not include air-conditioning ducts. The respondent's contention is that the phrase embraces both air-conditioning ducts and a dedicated network of sampling pipes. 117 This issue of construction is a major point in the case because, if the respondent's contention is correct, then the existence and use in the market at and before the priority date of smoke detection systems such as the VESDA E700 Mk II (with filter) and VESDA E700 Mk III and the Olsen D51B (which used air-conditioning ducts to draw air) leads to the conclusion (which I do not understand the applicant to dispute) that a number of the major claims of the specification are not valid because they lack novelty. 118 As far as the construction of the term "particles filter" is concerned, the dispute between the parties narrowed as the trial proceeded. At the beginning of the trial, the respondent argued that the insect screen in the Olsen D51B smoke detection system was a particles filter within the claims. For its part, the applicant argued that a particles filter was a filter which prevented the passage of particles of a particular size and the applicant relied on the Australian Standard known as AS 1670-1986 "Automatic fire detection and alarm systems - System design, installation and commissioning" ("AS 1670-1986") to support its submissions. The respondent no longer presses its argument that the insect screen in the Olsen D51B smoke detection system meets the description of a particles filter. For its part, the applicant does not argue that the foam filter in the Olsen D51B smoke detection system does not meet the description of a particles filter and I am satisfied on the evidence that it does meet that description. 119 What is left as an issue of construction is whether the term "particles filter" includes a sintered filter. That issue is important because the respondent relies on a discussion concerning a system to be installed at a Billy Guyatts store at Moonee Ponds (one sintered filter to be inserted in an inlet probe) as a prior publication which means that the alleged invention is not novel. Details of that discussion are set out below. 120 There was no real dispute about the proper construction of the terms, "detecting means" and "detection module". However, it is necessary for me to make some observations about the meaning of those terms.

Preliminary matters 121 A number of preliminary points which are relevant to the facts of this case should be made. First, the words in the claims which are in issue are ordinary English words. I heard evidence from a number of witnesses who were skilled in the industry at and before the priority date. Those witnesses gave evidence about the state of common general knowledge in the design, construction and use of fire detection systems in 1993 and of their understanding of the meaning of the principal claims in the specification. I have used the evidence about the state of common general knowledge at the priority date to inform my determination of the meaning of the claims. I have noted the evidence given as to the meaning of the claims but, as the authorities make clear, the meaning of the claims is a question for the Court and that must be a fortiori in a case such as the present where it is not suggested that any word or phrase bears a specialised meaning in the relevant industry. 122 Secondly, nothing in the body of the specification throws any light on the principal issue of construction in this case, namely, the meaning of "main duct means in the form of sampling duct means of a smoke detection system". The consistory clauses throw no additional light on the question of construction. That is my conclusion having read the specification and I did not understand either of the parties to suggest otherwise. 123 Thirdly, the specification contains a preferred form of the invention which is described in words and which is shown in two diagrams in figures 1 and 2. The preferred form is but one form of the invention. For example, the form described and shown relies on dedicated sampling pipes and contains a secondary duct means which is within the main duct means. As I have said, the latter feature was referred to as a coaxial arrangement. Having regard to the claims the alleged invention would include not only a coaxial arrangement but also a secondary duct means which joined the main duct means. Although the applicant asked various witnesses a number of questions about the preferred form described and shown in the specification, it did not suggest that the claims were to be read down in any way by reference to the preferred form.

"Main duct means in the form of sampling duct means of a smoke detection system" 124 A starting point is the dictionary definitions of the key words. The key words and their relevant meanings as set out in the Macquarie Encyclopedic Dictionary (2010, 2nd ed) are as follows: "duct" "1. any tube, canal, or conduit by which fluid or other substances are conducted or conveyed" "means" "1. (often construed as singular) an agency, instrumentality, method, etc, used to attain an end: a means of communication" "sample" as a noun "1. a small part of anything or one of a number, intended to show the quality, style, etc, of a whole; a specimen" "sample" as an adjective "3. serving as a specimen: a sample copy" 125 The Concise Oxford Dictionary (11th ed, 2006) contains the following definitions: "duct" "1. a tube or passageway in a building or machine for air, cables, etc." "means" "1. [treated as sing. or pl.] an action or system by which a result is achieved." "sample" "1. a small part or quantity intended to show what the whole is like. 2. a specimen taken for scientific testing or analysis." 126 The rival contentions as to the proper meaning of the phrase are as follows. 127 The applicant submits that air-conditioning ducts are not within the phrase "main duct means in the form of sampling duct means of a smoke detection system" because two important limitations arise from words within the phrase. First, the words "in the form of sampling duct means" limit main duct means to those main duct means which are designed and used for the purpose of taking samples. An air-conditioning duct is designed and used for the purpose of circulating conditioned air and not for the purpose of taking samples. Secondly, the last five words in the phrase "in the form of sampling duct means of a smoke detection system" emphasise that the sampling duct means must not only take a sample of air, but also be part of a smoke detection system. The applicant submits that an air-conditioning duct is part of an air-conditioning system and not a smoke detection system. 128 The respondent submits that there is no reason why an air-conditioning duct cannot be characterised as a duct which is part of an air-conditioning system and a main duct means of a smoke detection system. The respondent submits that the applicant's contention that an air-conditioning duct does not constitute a main duct means in the form of sampling duct means of a smoke detection system would have a great deal more force if the words used were "sampling duct" rather than "sampling duct means". The submission is that the use of the word "means" is fatal to the applicant's argument because it is a very broad word and it includes any item or object from which a sample is obtained and not just an item or object designed to provide a sample, for example, the dedicated network of sampling pipes referred to in the evidence. The respondent referred to Doric Products Pty Ltd v Lockwood Security Products Pty Ltd [2001] FCA 1877 at [35] where Hely J said "means" was a method for achieving an end. 129 There was a good deal of evidence called about the meaning of the phrase. I will briefly summarise the evidence, but in the end the question of construction is one I must resolve myself. 130 Dr Cole gave evidence that, unless there is an imperfection in the method of ducting, and, leaving aside the possible variation in concentration that could occur across a large zone, a sample of air of any size has the same smoke concentration and is fully representative of the smoke concentration within a protected zone. That, he said, was well understood in the industry in July 1993. 131 Dr Cole said that he did not think that the words "in the form of a sampling duct means" added anything to an understanding of the claims because "they are all sampling ducts at one level". Another way in which he put the point is that he said that he could not see the "differentiation" between a main duct and a sampling duct. Dr Cole agreed in cross-examination that he reads claims 1 and 3 by effectively deleting the words, "in the form of sampling duct means". Dr Cole agreed that, out in the trade, people might draw a distinction between an air-conditioning duct and a dedicated sampling pipe in terms of the range of equipment that they could apply to the application. A VESDA E700 smoke detection system could be applied to either, whereas an Olsen D51B smoke detection system could only be applied to an air-conditioning duct. 132 Wormald (Aust) carried on business in Australia from at least 1974 to 1990. In 1990 its business was taken over by Tyco International Ltd. Mr Jawerth worked for Wormald (Aust) from 1974 and then for Tyco International Ltd. As I understand it, his position has been technical manager, fire detection. 133 Mr Jawerth gave evidence about the meaning of the phrase in question. Eventually, he appeared to accept that an air-conditioning duct would not be a "main duct means in the form of sampling duct means of a smoke detection system". 134 Mr Johnson holds tertiary qualifications in science and fire protection. He is a member of professional organisations for engineers and fire protection engineers. He is well qualified in the area of fire or smoke detection. 135 Between 1975 and 1995 Mr Johnson held a range of positions at the Scientific Services Laboratory ("SSL") and its predecessors. This organisation was, at one time at least, part of the Federal Government Department of Housing and Construction. Among other things, the SSL provided advice to Commonwealth Government Departments about smoke detectors. Mr Johnson managed one of the major functions of SSL, namely, to test, type approve, quality assure and list a wide range of fire detection and suppression equipment. He also undertook investigations and applied research into fire detection and suppression system performance. It is clear that Mr Johnson had considerable experience in the fire detection industry in Australia. 136 Mr Johnson said that he did not consider calling a "main duct means" "a sampling duct means" had any significant bearing on the novelty of what was claimed. Mr Johnson said: "I do not understand how it can be considered inventive simply to call a duct which performs some purpose relevant to the function of a smoke detection system by a different name to that commonly given to it or simply on the basis that such duct performs other functions as well. The choice of whether to sample using separate dedicated pipes or to sample from the air-conditioner duct is a simple design choice, illustrated for example in the drawings forming part of the VESDA brochure of Exhibit MTC-3 of the declaration of Martin Terence Cole dated 22 December 1998, filed in this opposition. A copy of an illustrative page from that exhibit is now shown to me and annexed hereto as Exhibit PFJ-10. The reason why air conditioning ducting has been used where possible is because it obviously avoids the need to incur the expense of installing additional pipes." Mr Johnson said that he did not understand that the "main duct means" necessarily excluded an air-conditioning duct. He said that air-conditioning return ducts essentially take a sample of the air from a room or other protected area. 137 Mr Johnson gave evidence that suppliers of products for the fire protection industry and installation technicians would identify a sampling duct or pipe of a smoke detection system and an air-conditioning duct as different things. However, a skilled person would not consider a sampling duct or pipe of a smoke detection system to be necessarily different from an air-conditioning duct, "since they are both used to convey air which may or may not contain smoke". At any given point in time an air-conditioning or other duct contains only a sample of air from a room or protected area. He explained his evidence by saying a supplier or technician would view things from the perspective of the product involved, whereas the consultants and designers would view things from the perspective of the function performed, that is, sampling. 138 Mr Johnson was asked about the differences identified by Mr Girling and Mr Fox between a sampling pipe or duct of an aspirating smoke detection system and an air-conditioning duct. The points made by Mr Girling and Mr Fox, and Mr Johnson's responses were as follows: 1. Mr Girling and Mr Fox said that an air-conditioning system does not draw a sample of air from a room or other protected area, but over time it draws the whole of the air from the room or other protected area. Mr Johnson's response was that an air-conditioning system does over time replace most of the air in a room or protected area with either fresh air (in some cases) or recycled air plus 10 per cent fresh air. However, Mr Johnson said that, at any point in time, the air in an air-conditioning duct is a sample of the air from a room or other protected area. 2. Mr Girling and Mr Fox said that an air-conditioning system can be turned on and off and, for that reason, there may be point detectors in the rooms or other protected areas and outside the air-conditioning duct. By contrast, the aspirating smoke detection system which used a sampling duct operated all the time and there was no need for point detectors. Mr Johnson said that that was true in some but not all cases; there were cases where air-conditioning systems operated all the time. 3. Mr Girling and Mr Fox said that it was usual for an air-conditioning system to include a filter and a fan and to inject only 10 per cent fresh air. The filters used could be very coarse, or so fine as to filter out the particular products of combustion. Mr Johnson said that typically filters in air-conditioning ducts were fairly coarse. 4. Mr Girling and Mr Fox said that as, in the usual case, 10 per cent of the air was fresh air there was a prospect that air would contain smoke particles and trigger a false alarm. Mr Johnson agreed that there was a potential for that and that there had been work done to overcome the problem by having a detector dedicated to the incoming air. 139 At one point in his cross-examination, Mr Johnson agreed that an air-conditioning system was not within the phrase, "main duct means in the form of sampling duct means of a smoke detection system". Later, he appeared to retract that evidence and he said that an air-conditioning duct could be a "main duct means in the form of sampling duct means of a smoke detection system". 140 Mr Harold Piik-Wakeling is a fire systems engineer. He has worked in the fire protection field since the 1970s. 141 Mr Piik-Wakeling said that an air-conditioning duct could be a main duct means in the form of sampling duct means of a smoke detection system if it was "there for that purpose" or "as being an integral part of the detection system". Mr Piik-Wakeling was asked whether the smoke detection system shown in Figure 1 of the specification was separate from the air-conditioning system. As I have already said, this question was asked of other witnesses as well. Mr Piik-Wakeling agreed that it was separate. It will be remembered, however, that Figure 1 shows the preferred form of the alleged invention. 142 Mr Peterson said that he is a fire protection industry supplier and he would not identify a sampling duct or pipe of a smoke detection system and an air-conditioning duct as different things; "… I don't see that it's necessarily different things. Its - they're just tools to be used and it's a question of what are the particular circumstances." 143 Mr Knox said that he considered an air-conditioning duct could be part of a main duct means in the form of sampling duct means of a smoke detection system, "if an engineer doing an installation chooses to make it so". His evidence was: "The fact that it's an air-conditioning system does not mean it isn't being used as a main duct for the smoke detection system." 144 I should mention that Mr Knox did not come to Australia until shortly after the priority date. 145 I have already referred to evidence of Mr Girling and Mr Fox. 146 In addition to the evidence I have already summarised, Mr Fox agreed that in July 1993 there were two well-known ways of transporting air to smoke detectors and one was through air-conditioning ducts and the other was through dedicated sampling pipes. Mr Fox agreed that over time all of the air in a room or protected area will pass through dedicated sampling pipes and that at a given point in time both an air-conditioning duct and a sampling pipe will be taking a sample of air to the smoke detector. Mr Fox gave the following evidence: "I am putting the proposition to you that when the E700 device is used as a duct sampling device, the sample of interest is the one drawn from the area being monitored to the detection unit?--- That's absolutely right.

Thank you. Now, I want to put to you that when the E700 device is used in conjunction with air-conditioning duct work and when it is used in conjunction with sampling pipes, dedicated sampling pipes, the duct work and the pipes perform the same important function of taking that sample from the room or area under protection to the detector?---No. Air sampling duct - the air-conditioning duct work is performing a fundamentally different function and the aspirating smoke detection system is drawing a small sample from that.

The fundamentally different function is a collateral function, is it not, of providing air-conditioning?---Yes.

It does not - the fact that it is performing that collateral function does not change the fact that it is conveying the all important sample to the detection unit, does it?---No, it doesn't.

No. Both are means of transporting the relevant air sample to the detector?---Yes.

Now, I want to put to you , Mr Fox , that it is a distinction without a difference to suggest that air-conditioning duct work on the one hand is different to sampling pipes on the other so far as conveying sample from the room being protected to the detection unit?---The major difference would be that the aspirating smoke detection system has to meet requirements such as the ability to run for 24 hours in the event of a mains power failure and I'm not aware of any air-conditioning system which can do that.

That is not an aspect of the personality of air-conditioning duct work, I put to you, that makes any relevant difference so far as conveying the all important sample from the room being protected to the detection unit?---You're quite right until the event of an AC power failure, yes.

Now, what I want to put to you is that the expression in claim 3, the apparatus claim, main duct means in the form of sampling duct means is a reference to any duct work that delivers a sample of air from the protected area to the detector?---No, it's the sampling pipe entering the aspirating smoke detector." 147 Mr Barrett is a consultant electronic engineer. He was employed as a senior design engineer in the Research and Development department of IEI (Aust) between October 1990 and August 1993. He was closely involved with the smoke detector technology used and developed by IEI (Aust) and he was particularly involved with the design and development of the VESDA E700 Mk III. 148 Mr Barrett said that in his view the air inside an air-conditioning duct is the volume of air to be protected and not merely a sample of it. He said that the air-conditioning duct "represents" the entire volume of the air to be protected. He said that "sampling pipe" and "sampling duct" were used interchangeably in the industry. The word "means" was not a word used in the industry. Mr Barrett did not consider air-conditioning ducts to be part of a smoke detection system. They are part of the air-conditioning system; they are not sold as part of a smoke detection system. He reads the claims as meaning that the sampling duct means "was part of the system that the person who was implementing the patent would be passing on to his customer". Mr Barrett said that the words "main duct means of a smoke detection system" as a matter of English embraced any duct work that delivers a relevant sample of air from the protected area to the detector, but he said that no one in the industry would consider an air-conditioning duct to be part of "the fire detection system". He gave that evidence by reference to the identity of the party who supplied the component. 149 A number of witnesses were asked about AS 1670-1986 and, in particular, clause 4.3 which deals with sampling systems. Mr Johnson said, and I accept, that AS 1670-1986 was directed to "life safety" of the occupants of rooms directly affected and the rooms for which the detection system is placed. AS 1670-1986 does not deal with air-conditioning ducts; I was told they were dealt with by another Standard. That other Standard was referred to as AS 1688. AS 1670-1986 uses the word "duct" in a way which includes an air-conditioning duct and indeed may be restricted to air-conditioning duct. AS 1670-1986 does not use the word "means" in the relevant sense. AS 1670-1986 uses the word "sampling" but the word is not defined and there is nothing to suggest that it is not used in its ordinary sense. 150 None of the witnesses who gave evidence as persons skilled in the art at the priority date said that any of the terms in the claims in the specification were understood in the industry to have a meaning informed by AS 1670-1986 and none of the claims themselves refer to the Standard. 151 The applicant referred to the fact that prior to August 1999 the words "in the form of sampling duct means" were not part of claims 1 and 3. It referred to s 116 of the Act which provides that the Commissioner or a court may, in interpreting a complete specification as amended, refer to the specification without amendment. It is appropriate that I have regard to the amendment: Multiform Displays Ltd v Whitmarley Displays Ltd (formerly Reay and Davis Ltd) (1957) 74 RPC 260. At the same time the authorities are to the effect that it is neither useful nor legitimate to do this in circumstances in which the amended specification is clear: Martin and Biro Swan Ltd v H Millwood Ltd (1956) 73 RPC 125. 152 My conclusions in relation to the evidence are as follows. Before the priority date smoke detectors utilised a stream of air from air-conditioning ducts or from a network of dedicated sampling pipes. Before the priority date main duct means, sampling duct means, secondary duct means and smoke detection system were not terms of art or technical terms understood to mean particular things in the industry. AS 1670-1986 is of no assistance in resolving the issue of construction. The amendment to claims 1 and 3 in the specification is to be noted, but in the end I have decided that the meaning of the phrase is clear. It seems to me that I must decide the meaning of the phrase, "main duct means in the form of sampling duct means of a smoke detection system" having regard to what would have been known to the skilled addressee before the priority date but forming my own opinion as to the meaning of the words. 153 I have reached the conclusion that the respondent's construction of the phrase, "main duct means in the form of sampling duct means of a smoke detection system" is the correct one. In my opinion, the key to the resolution of the meaning of the phrase is the use of the word, "means". That is a word of the broadest connotation. It directs attention to the result or effect achieved by something, not the reason it was designed and built. It enables one readily to reach the conclusion that an item of plant and equipment might be used for more than one purpose. Subject to there being another duct, I have no difficulty in concluding that an air-conditioning duct falls within the words "main duct means … of a smoke detection system". I do not think that the addition of the words, "in the form of sampling duct means" operate to exclude an air-conditioning duct. I do not think any witness in this case disagreed with the suggestion that at any one time an air-conditioning duct carried a sample of air from a room or other protected area and plainly, it does. Again, the use of the word "means" with sampling duct is significant. It directs attention, not to some inherent or innate quality of an item of plant or equipment, but to its function. 154 In my opinion, an air-conditioning duct is capable of being a "main duct means in the form of sampling duct means of a smoke detection system".

"Particles filter" 155 As I have said, the applicant accepts that the foam filter at the top of the inlet pipe of the Olsen D51B smoke detection system is a "particles filter" within the claims in the specification, and the respondent accepts that the insect screen in the same system is not. The latter issue in particular occupied some time at the trial. 156 As I understood it, neither party suggests that the reference to "particulate impurity" and the removal of larger particles than those intended to be detected in claims 4 and 6 adds anything in terms of the meaning of "particles filter" in claims 1 and 3. 157 The only remaining question is whether a sintered filter falls within the description of a particles filter. In my opinion, having regard to the general nature of the term, and leaving aside questions of effectiveness, a sintered filter can be described as a particles filter. As I understood it, Mr Fox agreed with that conclusion, although he also said that he did not consider that they were not suitable filters in an aspirating smoke detection system.

"Detecting means" 158 There is no limit in the claims in the specification on the type of detecting means other than claims 12 and 18 which refer to a semiconductor optical emitter. The term, detecting means, would include all forms of smoke detectors (as distinct from heat or flame detectors) including ionisation detectors, optical (photo-electric) detectors using light obscuration and optical (photo-electric) detectors using light scattering. It would include different light sources including xenon lamps, light emitting diodes and lasers. It is not necessary that it be a high sensitivity smoke detector.

"Detection module" 159 There is no limit in the claims to a detection module of a particular size or shape or a module having particular features. The term is not a term of art or a technical term.

Relevant legal principles 160 At the relevant time, s 18(1)(b)(i) of the Act provided that a patentable invention is an invention that, so far as claimed in any claim: "(b) when compared with the prior art base as it existed before the priority date of that claim: (i) is novel; …" 161 At the relevant time, s 7(1) provided: "(1) For the purposes of this Act, an invention is taken to be novel when compared with the prior art base unless it is not novel in the light of any one of the following kinds of information, each of which must be considered separately: (a) prior art information (other than that mentioned in paragraph (c)) made publicly available in a single document or through doing a single act; (b) prior art information (other than that mentioned in paragraph (c)) made publicly available in two or more related documents, or through doing 2 or more related acts, if the relationship between the documents or acts is such that a person skilled in the relevant art in the patent area would treat them as a single source of that information; (c) prior art information contained in a single specification of the kind mentioned in subparagraph (b)(ii) of the definition of prior art base in Schedule 1." 162 The Act has a dictionary of expressions in Schedule 1 (see s 3) and in that dictionary prior art information was defined (relevantly) as information that is part of the prior art base in relation to deciding whether an invention is or is not novel, and prior art base was defined at the relevant time (relevantly) as: "prior art base means: (a) in relation to deciding whether an invention does or does not involve an inventive step: (i) information in a document, being a document publicly available anywhere in the patent area; and (ii) information made publicly available through doing an act anywhere in the patent area; and (iii) where the invention is the subject of a standard patent or an application for a standard patent - information in a document publicly available outside the patent area; and (b) in relation to deciding whether an invention is or is not novel: (i) information of a kind mentioned in paragraph (a); …" 163 For present purposes, the patent area is sufficiently described as Australia. 164 The definition of prior art base was amended by the Patents Amendment Act 2001 (Cth), to include information made publicly available through doing an act out of the patent area. That amendment does not apply in this case because it only applies where the complete application for the patent was made on or after 1 April 2002. The PTC application made on 1 August 1994 was itself a complete application. 165 The test for anticipation or want of novelty is the same as that for infringement and generally it is appropriate to ask whether the alleged anticipation would, if the patent were valid, constitute an infringement. That was the test enunciated in Harwood v Great Northern Railway Co (1865) 11 HLC 654; 11 ER 1488 and it has been applied ever since (see, for example, Meyers Taylor Pty Ltd v Vicarr Industries Ltd (1977) 137 CLR 228 at 235 per Aickin J). To satisfy the test, the prior document or act must involve or incorporate all of the integers of the claim under consideration. 166 In terms of what the prior document must disclose for it to defeat novelty, the classic statement of the proper approach is contained in the speech of Lord Westbury LC in Hill v Evans (1862) 4 De GF & J 288; 45 ER 1195; 6 LT 90; 31 LJ Ch 456; reproduced in 1 A IPR 1 at 6-7: "The question then is, what must be the nature of the antecedent statement? I apprehend that the principle is correctly thus expressed: the antecedent statement must be such that a person of ordinary knowledge of the subject would at once perceive, understand, and be able practically to apply the discovery without the necessity of making further experiments and gaining further information before the invention can be made useful. If something remains to be ascertained which is necessary for the useful application of the discovery, that affords sufficient room for another valid patent. By the words of the statute of James, it is necessary for the validity of a patent that the invention should not have been known or used at the time. These words are held to mean 'not publicly known or publicly used'. What amounts to public knowledge or public user is still to be ascertained. One of the means of imparting knowledge to the public is the publication of a book, or the recording of a specification of a patent. If, therefore, in disproving that allegation which is involved in every patent, that the invention was not previously known, appeal be made to an antecedently published book or specification, the question is, what is the nature and extent of the information thus acquired which is necessary to disprove the novelty of the subsequent patent? There is not, I think, any other general answer that can be given to this question than this: that the information as to the alleged invention given by the prior publication must, for the purposes of practical utility, be equal to that given by the subsequent patent. The invention must be shewn to have been before made known. Whatever, therefore, is essential to the invention must be read out of the prior publication. If specific details are necessary for the practical working and real utility of the alleged invention, they must be found substantially in the prior publication. Apparent generality, or a proposition not true to its full extent, will not prejudice a subsequent statement which is limited and accurate, and gives a specific rule of practical application. The reason is manifest, because much further information, and therefore much further discovery, are required before the real truth can be extricated and embodied in a form to serve the use of mankind. It is the difference between the ore and the refined and pure metal which is extracted from it. Again, it is not, in my opinion, true in these cases to say, that knowledge, and the means of obtaining knowledge, are the same. There is a great difference between them. To carry me to the place at which I wish to arrive is very different from merely putting me on the road that leads to it. There may be a latent truth in the words of a former writer, not known even to the writer himself; and it would be unreasonable to say that there is no merit in discovering and unfolding it to the world. Upon principle, therefore, I conclude that the prior knowledge of an invention to avoid a patent must be knowledge equal to that required to be given by a specification, namely, such knowledge as will enable the public to perceive the very discovery, and to carry the invention into practical use." 167 In Flour Oxidizing Company Ltd v Carr & Co Ltd (1908) 25 RPC 428, Parker J also addressed the issue of what must be contained in a prior publication in order for it to be an anticipation. His Lordship said (at 457): "But where the question is solely a question of prior publication, it is not, in my opinion, enough to prove that an apparatus described in an earlier Specification could have been used to produce this or that result. It must also be shown that the Specification contains clear and unmistakable directions so to use it." 168 There is a helpful statement of the relevant principles in the English decision of General Tire v Firestone. My summary of those principles is as follows: 1. It is necessary to compare the earlier publication with the patentee's claim and the earlier publication is to be interpreted as at the date of its publication having regard to relevant surrounding circumstances. 2. Both the patentee's claim and the earlier publication are to be construed as they would be at the respective relevant dates by a reader skilled in the art to which they relate having regard to the state of knowledge in such art at the relevant date. The construction of the documents is a question of law, but, in an appropriate case, the Court may be assisted by evidence as to technical matters. The question of novelty is a question of fact. 3. The patentee's claim will not be novel where the earlier publication: (1) discloses the same device; (2) contains a clear description of, or clear instructions to do or make, something that would infringe the patentee's claim if carried out after the grant of the patentee's claim; and (3) (where the prior inventor and the patentee have approached the same device from different starting points) contains directions which if carried out would inevitably result in infringement of the patentee's claim where carried out after the grant of the patentee's claim. 4. The patentee's claim will be novel where there are two ways of carrying out a direction in a prior publication both equally likely and one resulting in infringement of the patentee's claim and the other not; where the earlier publication does not contain clear and unmistakeable directions to do what the patentee claims to have invented. 169 The Court of Appeal in General Tire v Firestone said (at 486): "A signpost, however clear, upon the road to the patentee's invention will not suffice. The prior inventor must be clearly shown to have planted his flag at the precise destination before the patentee."

The prior art relied on by the respondent 170 The respondent relied on both information in documents publicly available in Australia and elsewhere and information made publicly available through the doing of acts in Australia. 171 The documents or acts included documents or acts related to the VESDA E700 units and documents or acts related to the Olsen D51B smoke detection system. 172 In relation to the VESDA E700 units the respondent contends that the following publications are prior publications which mean that the alleged invention was not novel: (1) the E700 Mk II Applications Manual; (2) the VESDA System Manual 1991; (3) iei Very early smoke detection apparatus VESDA E700 Mk II (Brochure); and (4) Guide to Building and Power Systems, Telecom Australia. 173 In relation to the VESDA E700 units the respondent contends that the following acts are prior disclosures which mean that the alleged invention was not novel: (1) Fire detection system using the VESDA E700 Mk I installed in conjunction with a dedicated network of sampling pipes at Billy Guyatts, Moonee Ponds ("Billy Guyatts Moonee Ponds"); (2) Fire detection system using the VESDA E700 Mk II installed in conjunction with a dedicated network of sampling pipes at Billy Guyatts, Blackburn ("Billy Guyatts Blackburn"); (3) Fire detection system using the VESDA E700 Mk I installed in conjunction with a dedicated network of sampling pipes at Radio Australia, Shepparton ("Radio Australia"); (4) Fire detection system using the VESDA E700 Mk II detector head installed at CERN. 174 In relation to the Olsen D51B smoke detection system the respondent contends that the following publication is a prior publication which means that the alleged invention was not novel: Olsen D51B Duct Sampling brochure 175 In relation to Olsen D51B smoke detection system the respondent contends that the installation of such units in conjunction with air-conditioning ducts in Australia prior to 30 July 1993 means that the alleged invention was not novel. 176 The respondent also relies on two publications which are unrelated to the VESDA E700 units or the Olsen D51B smoke detection system. They are the following: (1) United States Patent Office, Patent No 3,154,773 ("the Cerberus patent"); (2) Japanese unexamined patent publication 2-173896 ("the Nohmi patent"). 177 By the time of its closing submissions, the respondent had abandoned any reliance on the following: (1) The Olsen D51B in so far as it might be argued that the inlet pipe to the device was itself a "main duct means". (2) The Autronica Autrosense aspiration detector Type BW-50.

VESDA E700 Mk II and Mk III Smoke Detection Systems

Prior publications 178 As I have said, the VESDA E700 units were well-known products in the market before the priority date. The marketing of the products included the preparation and distribution of brochures and the sale of the product included the distribution of operating manuals and systems manuals. 179 The VESDA E700 Mk I smoke detection system did not include a filter. A brochure for the Mk I dated 1980 was tendered in evidence. It shows the VESDA E700 Mk I attached to air-conditioning duct by the use of two probes and the same in the case of a dedicated network of sampling pipes. However, as I understand it, because the VESDA Mk I smoke detection system did not include a filter the publication is not put forward as defeating novelty. 180 The VESDA E700 Mk II smoke detection system was initially sold without a filter. However, shortly after its introduction it was decided that a filter should be included. Again as with the VESDA E700 Mk I smoke detection system, the Mk II was marketed as being capable of being used with air-conditioning ducts, dedicated sampling pipes or in special applications. Dr Cole said filters became a regular feature in 1981. In his oral evidence he said 1983, "'84 at the latest". In the case of the VESDA E700 Mk II smoke detection system, the system was marketed during the 1980s as including a filter, an E700 VESDA Detector, a fan and a detector enclosure. The enclosure was said to be optional. 181 In terms of the evidence before me, the brochures for the VESDA E700 Mk II smoke detection system never showed probes from the detector to a dedicated network of sampling pipes. They showed all of the air from the dedicated network of sampling pipes entering the detector. They did show probes from the unit entering air-conditioning ducts. 182 The brochures showing the VESDA E 700 Mk I and Mk II smoke detection systems were widely distributed in Australia. Dr Cole said that about 10,000 were distributed to various customers, potential customers and distributors of IEI (Aust). Furthermore, 21,380 VESDA E700 smoke detection systems were manufactured before July 1993 and approximately 10,000 of these were sold by IEI (Aust) throughout Australia before July 1993. 183 IEI (Aust) also distributed an operating manual and a system manual in connection with the VESDA E700 units. They were provided to purchasers of those products in Australia before 30 July 1993. 184 An example of the operating manual for the VESDA E700 Mk II smoke detection system was put in evidence. It included the following information and documents: 1. A brochure for a VESDA E700 Mk II similar to the brochures previously referred to. The brochure shows a VESDA E700 Mk II (with filter) being used in association with air-conditioning ducts, dedicated sampling pipes and in specialist applications. 2. A Victorian Engineering Excellence Award. 3. An applications manual for a VESDA E700 Mk II. There is no doubt from this document and, in particular, that part of it headed "E700 Mk II Air Sampling Techniques" that the sample of air going into the detector could be gathered by a perforated pipe being placed in front of a return-air register or by a perforated pipe being installed within an air-conditioning duct by means of an airtight penetration or by way of sampling pipe networks (that is, a dedicated network of sampling pipes). There is also a reference to filters and the use of paper filters in environments where there is dust. 4. Scientific papers. 5. Copies of articles, correspondence concerning the E700. 185 An example of a system manual for a VESDA E700 and published by IEI (Aust) in 1991 was put in evidence. I do not need to go through the document in detail. In one of the diagrams (Figure 1.1b) air enters a filter in the shape of a flower pot, then goes through a detector and then through an aspirator. These items are shown in an enclosure of some type and I was told the dimensions of the enclosure were about the same as those of an ordinary brief case. As with the other documents there is reference to obtaining a sample of air by inserting probes into air-conditioning ducts or by a "network of ceiling-mounted pipes". 186 Dr Cole gave evidence of the use of VESDA E700 units with air-conditioning ducts and dedicated sampling pipes. He gave evidence of a number of sites in Australia where prior to 1993 a VESDA E700 unit was used in association with the ductwork of an air-conditioning system. He said that about half of the VESDA E700 smoke detection units were used in association with air-conditioning ducts and the other half were used in association with a dedicated network of sampling pipes. 187 The respondent also relies on a Telecom Australia document which has a date of issue of 18 March 1985. The title to the document is "Guide to Building and Power Systems Engineering Department, HQ" and it contains the following statements: "1. General. VESDA (Very Early Smoke Detection Apparatus) is a highly sensitive air sampling smoke detector which can be used to detect smoke in a protected area with much higher sensitivity than other smoke detectors. VESDA relies on air being sampled from the protected area by either a pipe network or from an air handling duct. 2. Sampling Systems 2.1 Pipe Network Sampling Systems consist of single or multiple pipe configurations in the protected area. Air is sampled through small holes in the pipes by fan assisted induction, and passed through the sensing head. 2.2 Duct Sampling Systems consist of a sensing head with one or two pipes inserted into the air stream of a return-air duct. The differential pressure between the input and output may be used to cause air flow through the sensing head, or a separate fan may be required. A Duct Sampling System is a specialized form of VESDA requiring considerable design input to ensure a continuous, reliable fire detection system. The assistance of Design Standards Branch, Headquarters should be sought for this type of system as its use is still being investigated. 3. System Design … 3.8 Air filtering capable of removing 90% of particulates in excess of 10 micron diameter shall be provided at the input to the VESDA sensing head. This filter removes dust particles but allows smoke to pass through." 188 It is perhaps useful at this point to recapitulate the following. When it was launched in 1979, the VESDA E700 Mk I smoke detection system was not fitted with a filter or a fan and it was not contained in a housing. It consisted of a metal detector chamber which had affixed to it a Xenon light source and a scattered light detector. It had brass or stainless steel inlet and outlet probes welded onto the detector chamber which were designed to be inserted into conduits or pipes carrying samples of air from the area to be protected. The VESDA E700 Mk II included an aspirator and all of the components were housed in a steel box. Shortly after it was introduced a paper filter was included. The VESDA E700 Mk III consisted of a plastic enclosure instead of a steel fan box and the "muffin" fan in the Mk II was replaced with a high-efficiency aspirator. In about 1993 a foam filter replaced the paper filter. 189 For the reasons I have already given, I have concluded that "main duct means in the form of sampling duct means" includes an air-conditioning duct. 190 The brochures for the VESDA E700 Mk II smoke detection system (and I take one marked "Copyright IEI (Aust) Pty Ltd 1988" as an example) make it plain that the device operates in relation to a stream of air referred to as a sample of air. The inlet probe into the air-conditioning duct means that only part of the air flows through the detector enclosure, through a particles filter and then through a detector. The brochure clearly refers to use of the smoke detector with "air-handling ductwork already installed" and shows a unit attached to air-conditioning duct work in a museum. 191 In my opinion, the features of claims 1, 3, 4 and 6 in the specification are shown. There are a number of air-conditioning ducts and therefore there is a plurality of sampling pipes and the features of claim 9 in the specification are present. There is a single detector and therefore the features of claim 10 in the specification are present. The detector appears to include a tubular housing and therefore the feature in claim 11 in the specification is present. 192 The operations manual included the applications manual. The latter document refers to "In-duct Detection" and the placing of a perforated inlet pipe in an air-conditioning duct (with airtight sealing grommets) and outlet pipe. Those pipes are connected to a VESDA E700 Mk II system. There is reference to a filter "before the E700 Detector" being used in places where there are high dust levels. 193 The operations manual describes the features in claims 1, 3, 4 and 6 in the specification. In addition, there is a plurality of sampling pipes (that is, air-conditioning ducts), a single detector and the detector includes a tubular housing. I note that in the section dealing with design improvements for the Mk II detector there is reference to a sampling chamber "which is essentially a round tube". 194 The Guide to Building and Power Systems reveals the features of claims 1, 3, 4 and 6 in the specification and has a plurality of sampling pipes and the detecting means is a single detector. 195 The systems manual which deals with a VESDA E700 Mk III unit reveals the features of claims 1, 3, 4 and 6 in the specification and has a plurality of sampling pipes, the detecting means is a single detector and the detector includes tubular housing. 196 In summary, the prior publications in connection with the VESDA E700 Mk II and Mk III units show the use of those units in connection with the ductwork of an air-conditioning system. I have concluded that an air-conditioning duct falls within the description of a "main duct means in the form of sampling duct means of a smoke detection system". In light of that conclusion, the prior publications defeat novelty in the manner I have indicated. 197 I do not understand the respondent to assert that any of the prior publications in relation to the VESDA E700 Mk II and Mk III units show a bypass arrangement in connection with a dedicated network of sampling pipes. The respondent does assert that there are prior acts involving a bypass arrangement in connection with a dedicated network of sampling pipes and it is to that topic that I now turn.

Prior uses 198 It is convenient to begin by identifying some important legal principles which are relevant to proof of prior use. 199 The applicant submits that in the case of an alleged prior use, there should be corroboration from an independent witness and, preferably, the presentation of records which corroborate the alleged prior use. It is not clear to me whether the applicant goes so far as to submit that corroboration was required as a matter of law. If it does go that far then I reject the submission. 200 The correct principle is that a prior public use must be strictly proved and evidence which is not corroborated must be scrutinised with care, particularly where it is evidence of events which occurred many years ago. In Commonwealth Industrial Gases Ltd v M.W.A. Holdings Pty Ltd (1970) 180 CLR 160 (at 165-166) Menzies J said: "It is not that I dismiss the evidence as deliberately untruthful - although I am disposed to think that the evidence relating to Ex 8 and Ex 9 - which was a less than accurate representation of Ex 8 - was not wholly frank - it is rather that I cannot accept as reliable, oral evidence relating to particular pieces of equipment to which some reference has been found in the records of the defendant company, and then, as if by unaided recollection of observations made up to twenty-eight years ago, that equipment has been identified and described by the witnesses. It is apparent that during the long period since the equipment was seen, the witnesses must have looked at hundreds, if not thousands, of unremarkable pieces of similar equipment, and I have no confidence in their stated recollections of particular pieces of equipment among those numbers." 201 In Nicaro Holdings Pty Ltd v Martin Engineering Co (1990) 16 IPR 545 at 556-557 Gummow J said that proving an alleged anticipation by the recollection of witnesses and by drawings in catalogues and brochures is to be approached with "some caution". 202 In Windsurfing International Inc v Petit (1983) 3 IPR 449, Waddell J (at 489) referred to the need to scrutinise evidence of an alleged prior public use with great care and said that such a use should be strictly proved. 203 The information must have been made "publicly available" through the doing of the act. The concept of information being made "publicly available" was recently considered by the Full Court of this Court in Insta Image Pty Ltd v K D Kanopy Australia Pty Ltd [2008] FCAFC 139; (2008) 78 IPR 20. The facts before the Full Court raised an issue as to whether an invention involving a collapsible canopy framework was made publicly available by reason of its use at public events such as motocross races and jet ski races. The Full Court identified the relevant principles at 44 [124]: "In respect of the issue whether information was 'publicly available' before the priority date, the following principles emerge from the cases: · The information must have been made available to at least one member of the public who, in that capacity, was free, in law and equity, to make use of it (PLG Research Ltd v Ardon International Ltd [1993] FSR 197 at 226 per Aldous J cited in Jupiters at [141]). (This test of communication to a member of the public who is free in law or equity to use the information as he or she pleases had been enunciated by the English Court of Appeal as early as 1887 in Humpherson v Syer (1887) 4 RPC 407 at 413 per Bowen LJ.)

· It is immaterial whether or not the invention has become known to many people or a few people (Sunbeam Corporation v Morphy-Richards (Aust) Pty Ltd (1961) 180 CLR 98 at 111 per Windeyer J). As long as it was made available to persons as members of the public, the number of those persons is not relevant. Availability to one or two people as members of the public is sufficient in the absence of any associated obligation of confidentiality (Fomento Industrial S.A. v Mentmore Manufacturing Co Ltd [1956] RPC 87 at 99-100; Re Bristol-Myers Co's Application [1969] RPC 146 at 155 per Parker LJ).

· The question is not whether access to an invented product was actually availed of but whether the product was made available to the public without restraint at law or in equity (Merck & Co Inc v Arrow Pharmaceuticals Ltd (2006) 154 FCR 31 (Merck) at [98]-[103]).

· In order to be 'available', information said to destroy novelty must be of a kind that would disclose to a person skilled in the relevant art all of the essential features or integers of the invention (cf RD Werner & Co Inc v Bailey Aluminium Products Pty Ltd (1989) 25 FCR 565 at 593-594).

· In order to be 'available', information said to destroy novelty must 'enable' the notional person skilled in the art at once to perceive, to understand, and to be able practically to apply the discovery, without the need to carry out further experiments in order to arrive at that point (Stanway Oyster at 581-582)." 204 With respect to the facts, the Court said (at 49 [151]): "The public was not denied access, and there was a means for the public to inspect the original. There was nothing to prevent a member of the public from going to its location at the back of the pits, and examining it sufficiently to understand its construction and its component features. There is nothing in the evidence to suggest that examination would not have revealed all the integers of the claimed invention including the mounts and pins as described in the Patent specification. The information gleaned from such an inspection would, for the purposes of practical utility, be equal to that given in the patent (Hill v Evans (1862) 31 LJ CL 456 at [7]; Merck at [111]-[112]). An inspection would enable a person skilled in the art to put the claimed invention into practice (cf Bodkin at [3790] and the cases there cited)." 205 The applicant referred to the decision of Gyles J in Delnorth Pty Ltd (ACN 051 954 977) v Dura-Post (Aust) Pty Ltd (ACN 101 287 512) (2008) 78 IPR 463. One issue in that case was whether information about a roadside post had been made publicly available by the doing of an act. In the course of his reasons, Gyles J said (480-481 [73]): "The present case is not like Jupiters, where the system was operating in what amounted to a public place and could be observed. In my view, the evidence does not enable any such finding to be made here. Even if it was left around the factory, nobody was invited to look at it and nobody would have had any occasion to take any notice of it. In any event, the matter was not pleaded in that way. Rather, the case turns on the principle that, if a product is made available to a member of the public without restraint at law or in equity as to the use of that product that is regarded as public disclosure. That principle has been applied for a very long time when various formulations of the statutory test have applied. In the present context, that would be the equivalent of making the information publicly available by an act. It is well-recognised that a duty of confidence in the recipient would negate the public nature of the act." 206 In the result in that case, Gyles J held that the person to whom the prototype had been shown was under a duty not to use it or disclose it without the consent of the person who had showed it to him. There was an appeal from the decision of Gyles J but not on this aspect (Dura-Post (Aust) Pty Ltd v Delnorth Pty Ltd [2009] FCAFC 81; (2009) 177 FCR 239). 207 It appears that a contractor can be a member of the public for the purposes of determining if information was made publicly available: Lux Traffic Controls Ltd v Pike Signals Ltd [1993] RPC 107. 208 Disclosure within a company (that is, to other officers or employees of the company) may not involve making information publicly available. Wood v Westaflax (Aust) Pty Ltd (1990) 20 IPR 387 was a case which involved a patent for ducting of the kind used in air-conditioning. The respondent claimed that the invention lacked novelty because the inventor had given a sample of the product to a Mr Williams of Heacon Products Pty Ltd outside Australia and Mr Williams had taken it back to Australia and shown it to, among other people, some of the employees of Heacon Products Pty Ltd including his superior, the managing director, and the sales manager. King J held that the disclosure to the employees was not sufficient to amount to publication (this case was a pre-1990 case and related to publication and not the concept of public availability). His Honour said (at 399): "As the disclosures of the invention by Mr Wood and others to Mr Williams took place overseas they cannot be relied on as prior publication in Australia. Furthermore Mr Williams was, in receiving the sample, acting as the duly authorised agent of his employer, and in that capacity brought it back to Australia, and also in that capacity showed it to his superiors and some fellow employees. The giving of the sample to him was in law the giving of it to Heacon Products Pty Ltd, and the showing of it to other employees of Heacon was not prior publication in Australia, as all persons who saw it did so in their capacities as agents of Heacon. The situation was equivalent to an individual showing the duct to himself." 209 As far as the alleged prior uses at Billy Guyatts Moonee Ponds, Billy Guyatts Blackburn and Radio Australia are concerned, the respondent's case relies heavily on the evidence of Mr Miles. In addition, some evidence relevant to those uses was given by Mr Petersen. 210 Mr Miles was employed by IEI (Aust) between 1992 and 1995 and by the respondent between 1995 and 2005. At the time he gave evidence, Mr Miles worked for a company in Western Australia which distributed, among other products, the VESDA products. The VESDA products were supplied by Xtralis. Mr Miles' company was Spectrum Technologies International Limited, and it had some association with a company in which Mr Petersen has an interest. 211 Mr Miles commenced an apprenticeship as an electrical fitter with K A Jessup Pty Ltd ("Jessup") on 7 December 1977. He was 17 years old. In 1980 he was in the third year of his apprenticeship. 212 In 1980 Jessup was approached by Billy Guyatts and asked to install a smoke detection system in its retail store at the corner of Sydenham Street and Holmes Road, Moonee Ponds, in the State of Victoria. 213 A short time after the request, the matter was discussed between Mr John Peterson of IEI (Aust) and Mr Alan Jessup, who was the principal of Jessup. It was decided to install a VESDA E700 Mk I smoke detection system in the store. IEI (Aust) was to provide the system and advice about the design and construction of the system on the premises. Mr Miles was to be part of Jessup's installation team. 214 A number of discussions about the proposed installation took place between members of Jessup and, on occasions, Mr Petersen of IEI (Aust) was present. Those from Jessup who were involved in the discussions were Mr Keith Jessup, Mr Bruce Arrowsmith (the foreman at Jessup), Mr Miles and another apprentice. 215 The equipment for the smoke detection system that was chosen by Jessup was a centrifugal blower as a vacuum pump and a sintered bronze filter. IEI (Aust) provided the detector chamber, its mounting system and the control system. Jessup obtained the pipework and fittings. Mr Peterson provided advice on the pipework and fittings and on their design. 216 The system which was installed by Jessup at Billy Guyatts Moonee Ponds, had the following features: 1. Air was drawn from the room or other protected area through 50 mm branch pipes. There was a sintered filter in each of the branch pipes at the point where they first drew air from the room or other protected area. 2. The branch pipes joined a trunk pipe. 3. The air travelled along the trunk pipe to an inlet probe (approximately 25 mm in diameter) for a Mk I detector. The inlet probe extracted a sample of air which was taken to the detector, tested and then returned to the trunk pipe through an outlet probe. 4. The main flow of air continued along the trunk pipe. 5. All the air from the trunk pipe, including the air returned to the pipe through the outlet probe was exhausted to atmosphere by an air pump situated beyond the outlet probe. 217 The system as I have described it does not embody one feature of claims 1 and 3 in the specification, namely, a particles filter disposed in the secondary duct means (being according to the respondent's submission, the inlet probe). This is the topic upon which the conversation deposed to by Mr Miles is significant. 218 Mr Miles said that prior to the decision to place sintered filters at the end of the branch pipes, there was a discussion within Jessup about the possibility of placing a sintered filter in the inlet probe instead of at the ends of each branch pipe. Those involved in the discussion were Mr Keith Jessup, Mr Bruce Arrowsmith and himself, and the perceived advantages and disadvantages of doing so were discussed. Ultimately, Mr Miles said that the idea was rejected because an economically commercial filter of the correct size was not available at the time. However, the respondent's case is that that discussion was a discussion about a bypass arrangement that embodied the features of claims 1 and 3 in the specification. 219 In the period between 1980 and 1983 Billy Guyatts' head office was in Alfred Street, Blackburn. 220 Jessup installed a VESDA E700 Mk I smoke detection system at the premises in about 1981. Mr Miles was one of the employees involved, and he described the features of the system which was installed in the following way: 1. Capillary tubes 8 mm in diameter were attached to a trunk pipe 100 mm in diameter which, by means of a fan at the end of the trunk pipe, drew air from the capillary tubes through the trunk pipe. 2. There was an inlet probe in the trunk pipe which led to a VESDA E700 Mk I detector with a flash tube assembly. 3. There was an outlet probe from the detector unit into the trunk pipe to carry air back into the trunk pipe. 221 About one year later, Jessup upgraded the smoke detection system at Billy Guyatts, Blackburn, by replacing the VESDA E700 Mk I detector with a VESDA E700 Mk II detector. Again, Mr Miles was involved in the work and he described the features of the upgraded system in the following way: 1. A VESDA E700 Mk II detector was used. 2. The PVC inlet and outlet probes which were 20 mm in diameter had attached to them two rubberised flexible conduit pipes which Mr Miles described as being like washing machine hoses. These conduit pipes led to the detector enclosure containing the VESDA E700 Mk II detector. 3. The flexible pipe was "sleeved" over the two 20 mm in diameter probes. I mention at this point that Mr Miles' drawing does not show this sleeved arrangement. 4. Part of the air flowed from the trunk pipe into the inlet probe, along the flexible conduit pipe, through a filter in the VESDA E700 Mk II detector box, further along the conduit pipe, through the detector, and back through the flexible pipe to the outlet probe and back into the trunk pipe. 5. The filter consisted of a paper element housed inside a PVC pipe. It was provided by IEI (Aust). 6. There was a small fan at the outlet end of the detector box. 222 If I accept Mr Miles' evidence (a matter I will come to), the upgraded system embodies the features of, inter alia, claims 1 and 3 in the specification. 223 Some time shortly after July 1993, Mr Miles was asked by IEI (Aust) to replace a VESDA E700 Mk I detector at the premises of Radio Australia in Shepparton, Victoria. He went to the premises and found a VESDA E700 Mk I system in the roof space of the transmitter building. The system had not been serviced for a long time and was partially dismantled. The system used a sampling pipe network and part of that network was dismantled. 224 Mr Miles said that by looking at what was there, he was able to reconstruct how the system would have operated. 225 There was a pipe coming from a protected area. It entered a steel box which had a fan behind a plate which acted as a seal and which divided the box into two. The air entered the second part of the steel box (that is, the part that had the fan in it) and some of the air was exhausted through vents on the back of the box. Part of the air was directed through a pipe adjoining the rear part of the box. This air flowed through the pipe and then through a filter and then to a VESDA E700 Mk I detector. The detector was mounted on a timber board which was attached to the southern wall of the roof space above the transmitter hall. 226 The question of access to the Radio Australia site was the subject of a good deal of evidence. The applicant tendered an affidavit of Mr Bruce Robert Wilson. He was not required for cross-examination. Relevantly for present purposes, Mr Wilson was employed at the Radio Australia site between 1959 and either 1993 or 1994. He performed various technical roles at the site. He said that sampling pipes led from each of the transmitters into the transmitter hall ceiling space where the detector unit was located. Mr Wilson said that the VESDA smoke detection system was installed in the early to mid 1980s, probably between 1982 and 1985. A filter was included at some stage. Mr Wilson referred to the area around the site as a rural area which could generate a great deal of dust. 227 Mr Wilson is the most reliable source of information as to access to the site, access to the transmitter building and access to the ceiling space where the VESDA E700 Mk I unit was located. I make the following findings of fact based on his evidence: 1. The site was potentially dangerous because of the nature of the operations and equipment on the site. There were the risks associated with systems carrying high frequency voltage and radiation risks. Access to the site was restricted. 2. At the relevant time, there was a security fence around the site and large gate at the entrance. 3. Access to the transmitter building was restricted. The doors were kept locked and access was supervised by technical staff. Visitors were provided with security, safety and radiation advice. 4. Prior to the 1980s, small visitor groups were allowed onto the site, but access was confined to a small mezzanine transmitter hall viewing area and in the transmitter hall. After that date, apart from staff, access to the site was restricted to authorised technical personnel and contracting staff such as electricians and plumbers. 5. Visitors were required to give prior notice of their intention to visit the site and obtain permission to do so. They were supervised to a greater or lesser degree while on the site. 6. The VESDA E700 Mk I unit was in the ceiling space and the detector box was located on and near the brick west wall of the ceiling space. Access to the ceiling was obtained by either of two ladders and associated manholes. At some stage in the 1990s restrictive access chains were added to both ladders. Access to the ceiling space was restricted to qualified technical staff who had a maintenance or operation requirement. 7. The general public had no right of access to the site, the transmitter hall and the ceiling space where the VESDA E700 Mk I unit was located. 228 At the time he swore his affidavit, Mr Nigel Holmes was transmission manager at ABC Radio Australia. He had been employed by the ABC since 1981 and he has held the position of transmission manager since 1993. During the 1980s and 1990s he visited the Shepparton site two or three times (and later, more frequently) a year. He gave his evidence by way of affidavit and he was not required for cross-examination. Mr Holmes deposed to the security measures in place at the Shepparton site. Other than the fact that he said that access into the ceiling space was either via a ladder with a trap door or a steep set of stairs with a handrail, his evidence about access to the site, transmitter hall and ceiling space was similar to that given by Mr Wilson. 229 Mr Howard Deer was employed by the ABC for approximately 30 years. In 1990, or thereabouts, Mr Deer worked within Radio Australia as acting controller of resources and distribution. He visited the Shepparton site on two or three occasions between 1990 and 1993. He gave his evidence by affidavit and he was not required for cross-examination. His evidence was not inconsistent with that of Mr Wilson or Mr Holmes. He made the point that the site was frequently upgraded or maintained and that involved, on occasions, external contractors visiting the site. He made the point that access to the site was largely restricted for safety reasons. He was not aware of any requirement that those accessing the site sign any form of confidentiality undertaking. 230 The critical aspects of Mr Miles' evidence are the conversation concerning Billy Guyatts Moonee Ponds and the precise features of the smoke detection systems he saw at Billy Guyatts Blackburn and Radio Australia. Those aspects are not corroborated by any other witness. There are no contemporaneous records of the conversation he deposed to or records or drawings of the smoke detection systems he described. 231 The other parties to the conversation in 1980 or 1981 were Mr Keith Jessup and Mr Bruce Arrowsmith. Neither gave evidence at the trial. The first time Mr Miles prepared plans of the smoke detection system at Billy Guyatts Blackburn, which he saw in 1982 or 1983, was in September 2009. When Mr Miles saw the smoke detection system at Radio Australia shortly after July 1993 it was partially dismantled. The first time Mr Miles prepared plans of that smoke detection system was in March 2008. 232 I have already referred to Mr Petersen. As I have said, Mr Petersen conducts a business in Western Australia and the business includes distribution of the VESDA products supplied by Xtralis. He is in regular contact with Mr Miles. Although the applicant tested Mr Petersen's recollection of events surrounding the smoke detection systems at Billy Guyatts Moonee Ponds and at Billy Guyatts Blackburn it did not challenge Mr Peterson's credibility with respect to those issues. Mr Peterson's evidence corroborates some of the relatively uncontentious aspects of Mr Miles' evidence. It was Mr Petersen who suggested to the respondent's solicitors that they contact Mr Miles. 233 Mr Petersen said that he was involved in the installation of a VESDA E700 Mk I smoke detection system with dedicated sampling pipes at Billy Guyatts, Moonee Ponds. He remembered the involvement of Jessup and Mr Miles and he recalled having conversations about the use and installation of the system. He remembered that it involved a trunk pipe and sampling pipes. He did not give any evidence about a discussion raising the possibility of placing a sintered filter in the inlet probe. 234 Mr Petersen said that he was involved in the installation of the VESDA E700 Mk I smoke detection system at Billy Guyatts, Blackburn and the replacement of that detector with a Mk II. He remembered climbing into the ceiling to inspect the ceiling space. Mr Petersen said that the 8 mm tubes were installed in parallel and all emanated from a manifold made by Festo. The manifold was connected to a trunk pipe. The system was in the ceiling and access was obtained by climbing a ladder and removing a tile in the ceiling. 235 Mr Petersen said that he was involved in arranging the installation of a VESDA E700 Mk I smoke detection system at Radio Australia. 236 I have considered Mr Miles' evidence very carefully. I do not think that he was trying to mislead the Court at any stage. Nevertheless, the matters and events about which he deposed took place many years ago and, as I have said, there are no contemporaneous records or drawings. Although I think that he genuinely believed the matters he gave evidence about, there were aspects of his evidence which lead me to think that his recollection about critical matters was not as clear as he considered. Some matters are more important than others, but it is the overall effect of Mr Miles' evidence which causes me to have doubts about his reliability. 237 There were three topics in particular where I thought Mr Miles' evidence was unclear and to some extent confusing, and where I think an element of reconstruction crept in. 238 The first topic was his evidence about the pipework and its size at Billy Guyatts, Blackburn. In his statutory declaration made on 27 March 2008, Mr Miles referred to 8 mm capillary tubes instead of the 50 mm "trunk" pipe used at the Moonee Ponds premises. In his affidavit affirmed on 22 May 2009 he corrected that statement to 50 mm "branch" pipe. In the same affidavit he referred to 8 mm capillary tubes, 50 mm diameter branch pipes and 100 mm trunk pipe at Billy Guyatts, Blackburn. In his affidavit affirmed on 25 September 2009 Mr Miles stated that at Billy Guyatts, Blackburn there were two types of pipe, namely, 8 mm capillary tubes and a 100 mm trunk pipe. Mr Miles sought to explain these errors and his correction of them in his affidavit of 25 September 2009, by reference to the fact that he had some old scribbled notes provided to him by his ex-wife. Those notes were not produced. 239 The second topic was Mr Miles' evidence about the replacement of the VESDA E700 Mk I smoke detection system with the VESDA E700 Mk II smoke detection system at Billy Guyatts, Blackburn and the location of the various components of the VESDA E700 Mk II system. It was not clear to me at the conclusion of that evidence what part of the system was in the ceiling space and what part was in the room, and what part was visible and what part was not visible. 240 The third topic was Mr Miles' evidence about the smoke detection system at Radio Australia, Shepparton. Part of his written evidence was struck out on the basis that it was hearsay. In giving that evidence Mr Miles appeared to have relied on conversations with employees at Radio Australia. At the end of Mr Miles' evidence, I was not satisfied that I could draw a clear line between what he himself saw and what he was told by employees of Radio Australia. 241 I should mention that the applicant relied on two other matters as suggesting that Mr Miles was not a reliable witness. They were Mr Miles' evidence about the trunk pipe entering the enclosure and the differences between Mr Miles' evidence about the layout of the Radio Australia site and Mr Wilson's evidence on that topic. I would not draw any adverse conclusion about Mr Miles' evidence based on those matters. The former is as likely as not a slip and, as to the latter, there are differences between a number of the witnesses as to the layout of the Radio Australia site and I do not think that those differences are of particular significance. 242 As I have already said, Mr Miles' evidence stands alone on critical matters. He said that he took photographs of the smoke detection system at Radio Australia, but no photographs were produced. He said that Mr Petersen designed the smoke detection system at Billy Guyatts Blackburn, and yet Mr Petersen did not give evidence of the features of that system. 243 In all the circumstances, including the time which has elapsed and the onus on the respondent, I am not prepared to act on the evidence of Mr Miles and find the alleged prior public uses relied on by the respondent. 244 In view of the above conclusions, there is strictly no need for me to consider whether, had I accepted Mr Miles' evidence, the features of the relevant claims were made publicly available. However, I will briefly address that matter on the assumption that I accepted Mr Miles' evidence. 245 As far as the conversation concerning the smoke detection system to be installed at Billy Guyatts Moonee Ponds is concerned, had I been satisfied that the conversation took place, I would nevertheless have found that the information was not made publicly available. I would have reached that conclusion by applying similar reasoning to that of King J in Wood v Westaflax Aust Pty Ltd (1990) 20 IPR 387 (see [208] above). 246 As far as the smoke detection system at Billy Guyatts Blackburn is concerned, had I been satisfied that the system embodied the features deposed to by Mr Miles, I would have nevertheless found that the information was not made publicly available. It seems to me that there is simply too much uncertainty in the evidence as to what part of the system was in the ceiling space and what part was in the cupboard and what could be seen and what could not be seen. 247 As far as the smoke detection system at Radio Australia is concerned, had I been satisfied that the system embodied the features deposed to by Mr Miles, I would, with some hesitation, have concluded that the information was made publicly available. As I have said, contractors can be members of the public and the evidence is that they had access to the site. Furthermore, the evidence of Mr Miles and Mr Deer satisfies me that the occupiers of the site did not expressly or impliedly impose a fetter of confidence on contractors who visited the site. 248 I reject the respondent's challenge to the novelty of the alleged invention by reference to the conversation concerning the smoke detection system to be installed at Billy Guyatts Moonee Ponds, and by reference to the smoke detection system at Billy Guyatts Blackburn and the smoke detection system at Radio Australia. 249 I turn now to consider the respondent's claim that a fire detection system using a VESDA E700 Mk II detector head and installed at CERN defeats the novelty of the alleged invention. 250 The respondent's case is that between 1987 and the priority date of 30 July 1993, Dr Cole made various presentations to industry groups in Australia about smoke detection systems and, in particular, VESDA smoke detection systems. During those presentations Dr Cole showed photographs of a VESDA E700 Mk II detector head installed at CERN. Those photographs showed a smoke detection system which (according to the respondent) embodied a bypass arrangement and all of the features of claims 1, 3, 4, 6, 8, 9, 10 and 11 in the specification. The publication of the photographs in Australia meant that they were part of the prior art base for the purposes of determining novelty. In the alternative, the respondent's case is that, should it be found that the photographs themselves are not sufficiently clear to show all the features of a bypass arrangement, then the photographs and Dr Cole's oral explanation of the features in the photographs was a sufficient disclosure of the features of claims 1, 3, 4, 6, 8, 9, 10 and 11 in the specification. 251 Dr Cole's evidence about the smoke detection system at CERN was challenged by the applicant in a number of respects. I deal with those challenges below. Although Dr Cole may have overstated the position in one or two respects, I find that he was an honest and reliable witness and well qualified within his area of expertise. 252 The first challenge to Dr Cole's evidence relates to the time at which he first disclosed his evidence about the smoke detection system at CERN. Dr Cole made a statutory declaration in the opposition proceedings on 22 December 1998. Since that date and up to 2 October 2009, he made a further five statutory declarations and he swore three affidavits. In none of them did he refer to the smoke detection system at CERN. The first time he dealt with that topic was in an affidavit he swore on 2 October 2009. That was within days of the commencement of the trial. No doubt that was unsatisfactory from a case management point of view, but the applicant asked me to go further and find that it reflected adversely on Dr Cole's credit and reliability in relation to his evidence as to the smoke detection system at CERN. 253 Dr Cole gave an explanation for the late disclosure of his evidence about the smoke detection system at CERN. He said that he ceased to have any involvement in the respondent in about 1999 and he was not part of the team that was involved in the development of the strategy concerning the opposition proceedings. He had not looked at his collection of photographs since 1997. It was probably in 1997 that his collection of photographs and slides were, at the request of an employee of the respondent, placed on two CD-ROMs. Dr Cole said that until shortly prior to trial, he focused his attention on published brochures and manuals and not on the presentations which he had made. He was prompted to look at his collection of photographs and slides by a conversation he had with the respondent's solicitors shortly prior to the trial. I accept Dr Cole's explanation for the late disclosure of his evidence about the smoke detection system at CERN. 254 CERN lies on the border of France and Switzerland. It is a unique facility. It includes a 27 km circular tunnel which is approximately 100 metres underground. Within the facility, there are electronic equipment rooms in the shape of large shipping containers and Dr Cole said that the rooms were called barracks. The barracks were air-conditioned and protected by smoke detection systems. 255 Dr Cole said, and I accept, that in 1987 and 1988 those smoke detection systems, or at least some of them, were VESDA smoke detection systems. 256 Dr Cole visited the CERN facility on 11 June 1987 and again on 8 June 1988. Dr Cole's diary entries support his evidence that he visited CERN on those occasions, as do a number of telex messages which were tendered in evidence. On his second visit, Dr Cole was accompanied by Mr Fox. I find that Mr Fox was mistaken in his written evidence that he visited CERN with Dr Cole in 1987. That was contrary to facts which were clearly established. In fairness to Mr Fox, he was disposed to accept that he was mistaken in the course of his oral evidence. On the occasion of the second visit on 8 June 1988, Dr Cole and Mr Fox discussed the VESDA smoke detection systems with people associated with the facility at CERN. However, they were unable to look inside any of the enclosures or cabinets because they were locked and there was no one present who could open them. 257 On the occasion of his first visit, Dr Cole saw a smoke detection system which included a VESDA E700 Mk II detector head. Dr Cole took photographs of the smoke detection system. That was his evidence and it is consistent with his practice at the time. There is no doubt on the evidence that Dr Cole took photographs of smoke detection systems he saw over the years and it is likely that he would have done so when he saw a VESDA smoke detection system at a facility with the unique features of CERN. Furthermore, Mr Fox said that during the late 1980s and early 1990s, Dr Cole usually carried a 35 mm camera and frequently took photographs of subjects of interest to him, using colour transparency film. 258 The two CD-ROMs previously referred to were tendered in evidence at the trial. Two photographs were produced from the CD-ROMs and they were exhibited to Dr Cole's affidavit sworn on 2 October 2009 as "MTC-57". I find that those photographs were taken by Dr Cole at CERN on 11 June 1987 and that they show a smoke detection system at the facility. Clearer copies of the photographs were tendered by the respondent and became exhibit R22. I should add that I accept Dr Cole's explanation for the fact that a slide showing the steel enclosure described below bears a date in 1988. That slide was tendered in evidence at the trial. 259 I do not think that there is any dispute that the two photographs show a smoke detection system (which was not operating at the time the photographs were taken) which collects a sample of air by the use of dedicated sampling pipes. In addition, there are other features of the system shown in the photographs which are not in dispute. However, there are features of the system which are in dispute. Those features relate to whether there is a main duct means and a secondary duct means or simply one duct and whether a device shown in one of the photographs is a particles filter or some other device such as a water or oil trap. 260 I start by describing the features shown in the photographs which are not in dispute. 261 The first photograph shows two sampling pipes in front of an air-conditioning grille. The pipes have small holes in them facing towards the direction of incoming air. The two sampling pipes join a main or trunk pipe. 262 The second photograph shows a steel enclosure or cabinet mounted on a wall. The cover of the enclosure is open and the contents of the enclosure are visible. A pipe adjoins the enclosure on the right hand side. Inside the enclosure the pipe joins a large impeller or fan. There is then a short vertical pipe which runs out of the top of the impeller. The short vertical pipe appears to have something at or near the top of it. There is a pipe or piece of flexible hose which runs at right angles from a position near the top of the short vertical pipe. This pipe or flexible hose runs in a horizontal direction to a glass or plastic container with a blue top. Adjoining the container on its left hand side is a piece of flexible hose which leads upwards to a detector head. The detector head has provision for an electrical connection, an inlet or outlet for the flexible hose and an inlet or outlet which, in the photograph, appears to have a cap on it. 263 Dr Cole gave evidence of the features of the system he saw on 11 June 1987 and which he said are shown in the photographs. He said that air would be taken in through the sampling pipes and it would pass along the trunk pipe and into the enclosure. After passing through the impeller the air would pass up the short vertical pipe. Dr Cole said that the short vertical pipe was open at the top and that the majority of the air would be expelled into the cabinet and thereafter out of the cabinet through vents in it. A small part of the air would pass through the horizontal pipe and then through the container with the blue top. Dr Cole said that that container was a filter and that, although the filter mechanism was not in the container, it is shown in the photograph resting on the left hand side of the bottom of the enclosure. The air would then pass into the detector. The inlet or outlet with the cap on it was in fact an exhaust outlet and the cap was there to protect the detector while it was being commissioned. 264 From the point of view of the challenge on the ground of lack of novelty, there are two critical aspects of the smoke detection system shown in the second photograph. The first is whether the short vertical pipe was closed at the top or open as Dr Cole claimed. If it was closed at the top the system does not have a main duct means and secondary duct means. In other words, it does not have a bypass arrangement. The second is whether the container with the blue top is a particles filter or some other device such as a water or oil trap. If it is not a filter then there is no particles filter disposed in secondary duct means. 265 The applicant submits that it can be seen from the second photograph that the short vertical pipe is closed at the top. In the alternative, it submits that it is unclear whether it is closed at the top or open. By the time of final submissions the respondent accepted that it is not clear from the second photograph whether the short vertical pipe was closed or open at the top. I think that proposition was accepted by Dr Cole in cross-examination. 266 I am unable to determine from the second photograph whether the short vertical pipe is closed at the top or is open but with a collar on it as was suggested by Dr Cole. The short vertical pipe appears to have something near the top of it but I cannot determine whether it is a cap or a collar. Furthermore, I am unable to determine from the second photograph whether the container with the blue top is a particles filter or some other device. The evidence in this case included diagrams and evidence of various types of filters, but it was not of such a nature that I could, from the general background, reach a conclusion by merely looking at the second photograph that the container with a blue top was or was not a particles filter. 267 The applicant submits that I should reject Dr Cole's evidence that the short vertical pipe was open because the smoke detection system would not work if that were the case. 268 Mr Fox and Mr Barrett gave evidence that if the top of the short vertical pipe was open, a "Venturi" effect would be created and that that would cause, or may cause, air to flow in the opposite direction to that intended. In other words, air would be drawn out of the horizontal pipe rather than pass through it. 269 Mr Fox said that he believed a Venturi effect would be created if the short vertical pipe was open, there was sufficient leakage from the cabinet and the exhaust outlet on the detector head was not capped. He qualified this evidence in cross-examination by saying that whether a Venturi effect would be created would depend on the diameters of the fitting. Mr Barrett also gave evidence of a possible Venturi effect. Mr Barrett, who is an electronics engineer, acknowledged in cross-examination that he was not an expert in the field and he said that he would defer to the opinion of Dr Cole having regard to the latter's expertise in the area. 270 Dr Cole is an expert in fluid dynamics. He explained the Venturi effect and certain principles formulated by Bernoulli. I accept Dr Cole's evidence and I accept that the system was capable of performing in the manner he described. 271 I have considered carefully Dr Cole's evidence of the features of the smoke detection system at CERN. I have borne in mind that the onus is on the respondent to establish the prior use and publication which it claims has the consequence that the applicant's alleged invention is not novel. As I have said, Dr Cole was an honest and reliable witness. I accept his evidence as to the features of the system. Mr Fox and Mr Barrett did not see the system, but they gave evidence of what they considered to be the features of the system. I prefer Dr Cole's evidence to their evidence. I should add that I accept Dr Cole's evidence that the reference in his diary entry for 11 June 1987 to "End closed" is not a reference to the top of the short vertical pipe. 272 I should at this point mention evidence given by Mr Mitchell. He appeared by video link from the United Kingdom. Mr Mitchell was employed by IEI (UK) between 1989 and 1994. His job was (as he put it) to set up smoke detection systems and to test them. He was not involved in designing smoke detection systems. From 1994 Mr Mitchell was employed by companies whose business involves the installation of aspirating smoke detection systems. Those companies have installed smoke detection systems for both Airsense Technology and the respondent. 273 Mr Mitchell was shown Dr Cole's photographs by a patent attorney in the United Kingdom. He described what he saw in the second photograph. The top of the short vertical pipe appeared to him to be "capped-off" and there appeared to be a moisture trap. As to the latter, he said that there was a little drain at the bottom of that item. He said that he had never seen a particles filter which looked like the container with the blue top, whereas he had seen moisture traps which looked very similar to the container with the blue top. 274 In cross-examination, Mr Mitchell agreed that it would be unusual for a system such as the system shown in the photographs not to have a particles filter. 275 Mr Mitchell was an honest witness but his expertise in terms of the design and function of smoke detection systems was quite limited. He has a level of practical experience, but it does not rival the expertise and experience of Dr Cole. I prefer the evidence of Dr Cole. 276 The findings set out above do not of themselves defeat the novelty of the applicant's alleged invention because the use at CERN was outside the patent area. At the relevant time, the prior art base for the purposes of determining novelty did not include an act outside the patent area. In order to succeed on this point the respondent must make out its allegation that between 1987 and 30 July 1993 Dr Cole made presentations to industry groups and that during those presentations Dr Cole showed the photographs and explained the features of the smoke detection system. Having regard to my findings as to what is and what is not shown in the second photograph, it is not sufficient for the respondent to establish that the photographs were shown. It must establish that Dr Cole explained the features of the system and, in particular, the bypass arrangement and the presence of the particles filter. 277 With respect to that issue, a number of matters are clearly established by the evidence. 278 I am satisfied that over the years, including between 1987 and July 1993, Dr Cole was an enthusiastic promoter of products of IEI (Aust) including the VESDA smoke detection system. Dr Cole was a man for detail and he kept detailed records by way of diary entries and a substantial collection of photographs and slides. He made regular presentations to industry groups and potential purchasers of the products of IEI (Aust). During the presentations Dr Cole would show the audience some of his photographs and slides and he would explain the features and no doubt, what he perceived to be the advantages of the products of IEI (Aust) including the VESDA smoke detection system. As I have already said, the two photographs of the smoke detection system at CERN were part of Dr Cole's collection of photographs and slides. 279 Dr Cole gave evidence of his presentations and the fact that he made presentations on a regular basis was supported by a number of his diary entries. Other witnesses gave evidence of the fact that Dr Cole gave regular presentations and these witnesses included Mr Petersen, Mr Miles, Mr Fox (who spoke of presentations in England, Ireland and France), and Mr Julian Whitta. 280 IEI (Aust) had premises at Clayton, Victoria. Dr Cole said, and I accept, that in the auditorium at those premises he gave the following presentations: 1. Presentations on 22 and 23 June 1987 to Telecom employees from around Australia; 2. A presentation on 5 September 1988 to Asian distributors; and 3. A presentation on 7 September 1988 to persons associated with the Commonwealth Fire Board. Dr Cole also gave presentations at the following venues: 4. A presentation on 23 February 1989 in Adelaide to people associated with the fire industry; 5. A presentation on 16 March 1989 at Sydney University, New South Wales, to persons associated with the hospitality industry; and 6. A presentation on 7 April 1989 in Western Australia with people associated with Telecom. 281 Dr Cole said, and I accept, that there were other presentations and that the audiences included representatives of Wormald (Aust), other distributors, installers, designers of systems, architects and representatives of institutions such as Telecom and fire brigades. All of Dr Cole's presentations were made as part of the promotion of the VESDA products and without any obligations of confidence imposed on members of the audience. 282 Dr Cole said that at his presentations he displayed the two photographs of the smoke detection system at CERN. He said that he discussed the features of the system shown in the two photographs and that he mentioned the fact that a majority of the air passed out of the top of the short vertical pipe. He mentioned the fact that a collar around the top of the T-piece narrowed the pipe at that point to control the proportion of air diverted into the horizontal pipe. One of the features of the system was, according to Dr Cole, the filter and he said that he mentioned the features of the system. 283 Mr Fox said that he attended presentations made by Dr Cole in England, Ireland and France between 1987 and July 1993. He had no recollection of the second photograph being shown, although he recalls other photographs being shown. He believed he would have remembered the photograph and the explanation Dr Cole said he gave when he showed the photograph if this had taken place. 284 Mr Julian Whitta is a graphic designer. He was employed by IEI (Aust) between 1989 and 1992 as a desktop publisher. He was responsible for preparing product and system design illustrations for the VESDA products and the preparation (with another) of the VESDA system manual. Mr Whitta said that although he had seen the first photograph during the course of his employment he had never seen the second photograph. He was aware that Dr Cole made presentations and during the presentations he presented 35 mm slides on a projector and spoke to various photographs. He in fact attended two presentations at IEI (Aust)'s auditorium. He does not recall any explanation about the installation at CERN. 285 Mr Whitta was an honest witness. However, his evidence does not establish that the second photograph was not in existence before the priority date. In fact, the evidence is overwhelming that it was in existence before the priority date. There is Dr Cole's evidence, the date of the slide and the evidence of Mr Petersen and Mr Miles. Mr Petersen recalls discussing VESDA E700 Mk II units at CERN with Dr Cole and seeing the two photographs in the late 1980s. Mr Miles said that shortly after he joined IEI (Aust) in 1991, he attended one of Dr Cole's presentations and Dr Cole showed the two photographs. I accept Mr Miles' evidence on this point. 286 I note Mr Whitta's evidence about what he sees as the features of the systems shown in the second photograph. However, in view of the fact that his area of expertise is not the design of smoke detection systems his evidence does not advance the matter very far. Mr Whitta's evidence supports the conclusion that the photographs taken at CERN would have been shown by Dr Cole (Mr Whitta described the application at CERN as "technically interesting") and that Dr Cole was in the habit of explaining at length the features of the systems he displayed in his slides and photographs. 287 I accept Dr Cole's evidence that between 1987 and 1993 he made presentations in Australia to industry groups and prospective purchasers. I find that at those presentations information was given to the audience without any obligation of confidence being imposed. I find that at a number of these presentations, Dr Cole showed the audience the two photographs of the smoke detection system at CERN. Dr Cole may have overstated the position when he said that he did this at all the presentations and this may explain the evidence of Mr Fox and Mr Whitta referred to above. Nevertheless, I am satisfied that he did display the photographs on a number of occasions. I am also satisfied that Dr Cole explained the essential features of the system when showing the photographs, including the opening at the top of the vertical pipe and the filter. Although Dr Cole did not give evidence of precisely what he said about the filter, he said, and I accept, that he mentioned the features of the system and that the filter was a feature of the system. 288 It follows from these findings the features of claims 1, 3, 4, 6, 8, 9, 10 and 11 in the specification were publicly disclosed in Australia before the priority date when Dr Cole showed the two photographs and explained the features of the smoke detection system at CERN.

Prior publication and prior use 289 Mr Jawerth produced (among other documents) an Olsen D51B Duct Sampling Unit brochure. The brochure was freely available in Australia before 1993 and it describes a smoke detector used in association with an air-conditioning duct. Relevant excerpts of the brochure are as follows: "The D51B Duct Sampling Unit is designed to sample smoke in air conditioning ducts and pass it through a suitable Smoke Detector. It is used for detecting smoke in areas serviced by air conditioning systems. It is also used to detect smoke being inadvertently supplied to an area via the air conditioning.

• Removable dust filter for easy cleaning or replacement.

The Duct Sampling Unit mounts directly to the outside of the duct with its sampling tubes protruding into the duct. A clear polycarbonate cover allows easy inspection of the detector, including its alarm indicator LED. The unit is fitted with a photoelectric detector to detect visible smoke at very low levels. It is designed to respond to a predetermined smoke density threshold over a wide range of air velocities and temperatures. The unit contains a terminal box allowing ease of termination and connection of an optional remote LED.

Air from the duct is collected through a slot (facing the direction of airflow) in a sampling tube Pressure build-up at this point causes smoke to be forced through the tube into the sealed housing. It then passes through the detector chamber. A baffle arrangement ensures that the detector cannot be bypassed. Smoke is exhausted through a short tube back into the duct. The photoelectric detector contained in the sampling unit operates on the Light Scattering principle where pulsed light is prevented by a light trap from reaching a Silicon Photo Diode receiver. Smoke entering the detector scatters the light pulses into the receiver and the signal produced is evaluated against an alarm threshold." 290 The Olsen D51B duct sampling units were supplied in Australia prior to July 1993. The Olsen units were offered for sale in Australia from the mid 1980s and Mr Jawerth estimated (although he was not directly involved in sales) that about 500 units had been sold in Australia before July 1993. Mr Jawerth said, and I accept, that the Olsen units were well known in the fire detection industry before July 1993. They were supplied with two filters at the end of the sampling pipes where they extend into the enclosure. The filter at the outlet pipe is a spare filter and is removed when the unit is installed. 291 Mr Jawerth produced an example of the Olsen unit and it was received in evidence and marked exhibit R21. 292 The brochure for the Olsen D51B duct sampling unit disclosed the features in claims 1, 3, 4 and 6 in the specification. It also disclosed a plurality of sampling pipes and a single detector. 293 The Olsen D51B unit contained all of the features of claims 1, 3, 4 and 6 in the specification. It also contained, when installed, a plurality of sampling pipes. There was only a single detector and it included a semiconductor optical emitter.

The Cerberus Patent 294 The Cerberus Patent bears the title "Fire Alarm with an Aerosol Indicator for Detecting Combustion Products Suspended in the Air". It was filed in the United States Patent Office on 23 February 1961. The patent was issued and published in 1964 and it became open to public inspection at the Australian Patent Office on 9 February 1965. 295 The patent relates to a fire alarm system with an aerosol indicator for detecting combustion products suspended in air. In the body of the patent, various types of aerosol or smoke detectors, including detectors using an ionisation method and detectors using photoelectric methods, are identified. The problem identified is the effect on a fire alarm system if the air contains contaminants such as dust, soot, vapours or the like. It is said that such a situation can lead to false alarms and the soiling of the indicator or detector. The solution proposed in the body of the patent is a filter which would filter out dust or soot particles, but would allow smoke particles to pass through it. The following statement appears in the body of the patent: "According to the teachings of this invention the disadvantageous influence of the foreign particles frequently present in air is overcome by causing the air to first pass through a filter before it reaches the indicators. The fire alarm according to the present invention is characterized by the fact that a filter is provided through which the gas to be tested reaches the aerosol indicator under the influence of a pressure difference created across said filter. The filter is preferably designed in such a manner that it will allow at least the majority of the aerosol particles having a diameter smaller than one m to pass, while it retains the majority of particles having a diameter of more than five m. It has been found that a fire may be reliably indicated by means of aerosol indicators even in very dusty or contaminated premises if these preconditions are met." 296 At the end of the patent there are four drawings which are labelled Figures 1, 2, 3 and 4. Figure 3 shows an ionisation detector with a filter facing the flow of air and arranged coaxially in what is said to be a conduit, line or duct. The arrows on Figure 3 indicate that air passes through the conduit, line or duct and that part of the air passes through the filter and then through the detector (said to be two electrodes arranged in a tubular housing) and part of the air passes through the conduit, line or duct on either side of the tubular housing. The body of the patent contains the following statements as to what is shown in Figure 3: "FIGURE 3 shows an ionization fire alarm arranged, by way of example, in a conduit or line;

"FIGURE 3 shows a further embodiment of an ionization fire alarm. The electrical members are arranged in a manner similar to FIGURE 2, so that for clarity in comprehension the same reference numerals have been employed. The two electrodes of the indicator are arranged within a tubular housing 23 which may be arranged, for example, in a duct or conduit. The gas to be tested for combustion products flows through the duct in the direction indicated by the arrows. Provided at the side of the housing 25 which faces the incoming air stream is a filter 21 which retains the aerosol particles having a diameter of, for example over five m while the particles having a smaller diameter are allowed to pass. In the embodiment according to FIG. 3, the filter 21, furthermore, performs the function of reducing the flow within the tube 23. This is desirable because excessive flow may change the relationship between the electrodes 14 and 15 so as to reduce indicator sensitivity.

It may be appreciated from the examples disclosed that, either an existing flow or, a pressure difference is employed to pass the air to be tested through the filter, or means may be provided to produce such a pressure difference (FIGURES 1 and 2)." 297 The respondent's submission is that the Cerberus patent contains all of the features in claims 1, 3, 4, 6 and 10 in the specification. That submission is correct if there is "a main duct means in the form of sampling duct means of a smoke detection system". The respondent submits that there is because the conduit, line or duct referred to in the Cerberus patent and shown in Figure 3 includes both an air-conditioning duct and a dedicated sampling pipe. In view of my construction of "main duct means in the form of sampling duct means of a smoke detection system" the Cerberus patent will defeat the novelty of the alleged invention if the conduit, line or duct includes an air-conditioning duct (whatever else it may be). The applicant accepts that conduit, line or duct in the Cerberus patent includes an air-conditioning duct and I think that concession is correct. It follows that the Cerberus patent anticipates claims 1, 3, 4, 6 and 10 in the specification. 298 It is appropriate that as far as possible I consider all arguments put to me. I will therefore consider the matter on the assumption that my construction of "main duct means in the form of sampling duct means of a smoke detection system" is incorrect and that the words apply and only apply to a dedicated sampling pipe or network of sampling pipes. On this assumption, the question is whether the Cerberus patent contains a clear and unmistakeable direction to construct a detector of the type described in the patent in a dedicated sampling pipe or network of sampling pipes. 299 I will briefly refer to the evidence given by various witnesses. 300 Dr Cole gave evidence that to implement what is shown in Figure 3 in the Cerberus patent a pressure difference would have to be introduced across the main duct or conduit to cause the air to flow in that direction. In his opinion, the main duct was probably part of a smoke detection system consisting of both a device that causes the air to flow along the main duct means and the device shown in Figure 3. He said that an obvious way of generating the airflow through the main duct means was an aspirator before or after the detection device. Interpreted in this way, Dr Cole said the Cerberus patent contained all the features in the specification. Dr Cole said that Figure 4 in the Cerberus patent clearly showed an aspirated smoke detection system. 301 Dr Cole agreed in cross-examination that there was nothing in the Cerberus patent which stated that the large duct shown in Figure 3 was to be a main duct means in the form of a sampling duct means of a smoke detection system. He said that the Cerberus patent was "silent on the issue". The inability to be certain may explain why Dr Cole said in his evidence in chief that the main duct was "probably" part of a smoke detection system. Dr Cole agreed that he had seen the specification and commented upon it before he considered the Cerberus patent. 302 Mr Jawerth's evidence as to how he interpreted the Cerberus patent was similar to that given by Dr Cole; he said that the large duct shown in Figure 3 was probably part of a sampling system. I think it is fair to say that Mr Jawerth was less inclined to accept that the Cerberus patent was silent on the nature of the large duct shown in Figure 3 and more inclined to think that it included a sampling duct as distinct from an air-conditioning duct. Mr Jawerth accepted that ionisation detectors were put in air-conditioning ducts in the 1960s, although he made the point that they did cause problems. 303 Mr Johnson said that he could not find anything in the Cerberus patent which told the reader what the large duct shown in Figure 3 was. He agreed that it could be either an air-conditioning duct or a main duct means in the form of a sampling duct means of a smoke detection system. He did say it was less likely in about 1975 to be an air-conditioning duct because of the problems experienced in putting ionisation units in air-conditioning ducts. However, Mr Johnson accepted that in the 1960s detectors were more likely to be installed in air-conditioning ducts than any other form of duct. He said that in 1964 it was as likely as not that Figure 3 was intended to illustrate the installation of an ionisation detector in an air-conditioning duct because it was not until some years after that date that it became the practice not to install ionisation detectors in air-conditioning ducts because it became clear that airflow affected the sensitivity of detectors. 304 Mr Fox said that because Figures 1, 2 and 4 showed aspirators and Figure 3 did not, he believed Figure 3 instructed him that the ionisation detector was to be placed in an existing duct. Mr Fox said that Figure 3 did not illustrate a detection module, nor was there any indication that the large duct may be a sampling duct means. Mr Fox agreed with Mr Girling's statement that the teaching of the Cerberus patent was that all of the air would be drawn through the filters. I will come back to this point. 305 In cross-examination, Mr Fox seemed to agree that the reference to a conduit, line or duct in the Cerberus patent included an air-conditioning system and a duct which was not part of an air-conditioning system. 306 Mr Barrett said that he did not think that there was anything in the Cerberus patent to indicate that the large duct shown in Figure 3 was a sampling duct or conduit of an aspirating smoke detection system. In fact, he found a passage suggesting the air was the volume of air to be sampled and not a test sample thereof. He concluded that the large duct was a pre-existing conduit or line and not a main duct means in the form of a sampling duct means of a smoke detection system. In his opinion the focus of the invention was the filter which could be cleaned by blowing the air in the opposite direction and it was not an attempt to prevent filter-clogging through the use of a bypass arrangement. 307 Mr Barrett seemed to agree that the filter and indicator or detector were capable of being used in a conduit, line or duct and that those terms were apt to include an air-conditioning duct or a dedicated sampling duct. 308 Mr Girling said that there was nothing in the Cerberus patent to indicate that the device shown in Figure 3 was in a sampling pipe or duct and in fact the indications were that it was to be placed in an existing duct, conduit or line. 309 The applicant submits that the Cerberus patent should be read at the date it was issued and published, being 1965, rather than (as the respondent submits) the priority date, being July 1993. Whether a prior publication alleged to defeat novelty should be read at the date of its publication or at the priority date is a matter which has not been resolved in the authorities: Re ICI Chemicals & Polymers Ltd v Lubrizol Corporation (2000) 106 FCR 214 at [41]-[46]; EI Dupont De Nemours and Co v Imperial Chemical Industries Plc (2002) 54 IPR 304 at [61]-[62]; General Tire v Firestone at 485. I do not think I need to resolve this issue because it seems to me that on any view the conduit, line or duct referred to in the Cerberus patent includes an air-conditioning duct. The patent refers to a duct and envisages the use of an existing flow. In other words, I think that whether the Cerberus patent is read as at 1964 or as at July 1993 it includes an air-conditioning duct having regard to the reference to conduit, line or duct. 310 The focus of the invention in the Cerberus patent is the addition of a filter designed to reduce false alarms and damage to the detector. The invention is quite specific as to the size of the filter and its function. There are then four examples of preferred embodiments of the invention. None of the embodiments in Figures 1, 2 or 4 involve air bypassing the filter. There is no mention in the body of the patent of air bypassing the filter or of a bypass arrangement whereby the life of the filter is prolonged. 311 The words "conduit", "line" or "duct" are wide enough to include a dedicated sampling pipe. However, the law requires that before a prior publication has the effect of defeating novelty there must be a clear and unmistakeable direction to the skilled reader such that if the directions in the Cerberus patent were followed that would result in the use of a detector with a filter in a dedicated sampling pipe. I do not think the Cerberus contains such a clear and unmistakeable direction. 312 On the proper construction of the words "main duct means in the form of sampling duct means of a smoke detection system" the Cerberus patent is an anticipation in relation to claims 1, 3, 4, 6 and 10 in the specification. Had the applicant's construction of those words been the correct one then the Cerberus patent would not be an anticipation.

The Nohmi Patent 313 The Nohmi patent, as it was referred to in the evidence, is a Japanese (Unexamined) Patent Publication (Kokai) No 2‑173896. "Kokai" refers to a published but unexamined Japanese patent application. The title of the invention is "Fire Alarm Device". 314 Mr Shinichiro Iskinawa and Mr Yoshifumi Sachi gave evidence about the practice of the Japanese Patent office and the National Diet Library, and I am satisfied that the Nohmi patent was published in Japan on 5 July 1990, or shortly thereafter, and certainly before July 1993. It was available to the public before the priority date of 30 July 1993. Furthermore, I am satisfied on the evidence that the document tendered in evidence is an accurate translation of the Nohmi patent. 315 The subject of the Nohmi patent is a fire alarm device which comprises an aquatic filtering unit, a suction pipe and a light-scattering type or light-extinction type smoke sensor. The invention relates to a fire alarm device which is used in poor environments where there is a large amount of what is called "environmental noise" such as vapour, oil, mist and dust. Examples of such environments are given in the Nohmi patent and they include a rolling mill of an iron works, a machine processing plant, a printing plant, and a cement plant. 316 The problems said to be solved by the invention are the elimination of false alarms and damage to the sensor caused by environmental noise. Broadly speaking, the method for solving the problems is the drawing of air through an aquatic filter. 317 The Nohmi patent has three drawings which are referred to as Figures 1, 2 and 3. Figure 1 shows an embodiment or form of the invention, while Figures 2 and 3 show fire alarm systems established for the purpose of conducting experiments. The results of the experiments are set out in a table which is identified as Table 4. 318 The respondent's case is that the Nohmi patent and, in particular, Figure 3, show all of the features of claims of 1, 2, 3, 4, 5, 6, 7, 10, 13 and 16 in the specification. 319 A brief description of what is shown in Figure 3 is as follows. At the end of the system shown in Figure 3 is an aspirator which sucks air through the system. It is located downstream of the items forming the system. The air to be tested is drawn from an area by way of holes in what appears to be a dedicated sampling pipe. The air travels down a pipe and then through an aquatic filter. After passing through the aquatic filter the air travels through a small pipe and into a chamber which contains a sensor or detector. The drawing shows that the sensor or detector has a paper filter at its inlet point and it does not occupy all of the space within the chamber. The drawing suggests that there is room for air to bypass the paper filter and the sensor or detector and pass into the pipe which leads to the aspirator. At least some of the air which enters the chamber must pass through the paper filter and into the sensor or detector for the system to work. 320 The respondent contends that Figure 3 shows a bypass arrangement. The space in the chamber on either side of the paper filter and the sensor or detector is a main duct means in the form of sampling duct means of a smoke detection system and the paper filter and the sensor or detector are secondary duct means arranged coaxially rather like the arrangement in Figure 2 of the specification. Only part of the air would pass through the paper filter and into the detecting means. 321 There was a great deal of the debate in the evidence about whether the filter and the sensor or detector occupied the whole of the chamber or, as Figure 3 suggests, only part of it. There are arrows in Figure 3 showing the direction in which the air will travel, but there are no arrows inside the chamber showing air travelling on either side of the filter and the sensor or detector. 322 The written description of what is shown in Figure 3 does not provide any material assistance. There is no reference to a bypass arrangement. The chief feature of the invention is the aquatic filter. In referring to Figure 3, the written description provides: "Then, in a similar manner to that of the experiment example shown in Fig 2, this air is passed through the aquatic filtering unit 10 and the sampling chamber 17, and is then discharged to the outside with the suction pump 19.

For the smoke sensor 5 installed in the sampling chamber 17, a high-sensitivity light-scattering type smoke sensor is used to make it possible to securely sense the smoke that has been diluted after being sucked through the plurality of small holes 20a. Further, a paper filter F is provided at the air inlet for protecting the sensing section." 323 As with the Cerberus patent, a number of witnesses skilled in the art before the priority date gave evidence as to what they considered to be features of the Nohmi patent. 324 Dr Cole gave evidence that in his opinion Figure 3 could be viewed as having all the essential features in the specification, namely, a sampling chamber (that is, a main duct means in the form of a sampling duct means of a smoke detection system) a filter and sensor or detector (that is, a secondary duct means) filtering part of the air and a detecting means downstream of the filter. Dr Cole said that what was significant was that only part of the air would pass through the filter and sensor or detector. The use of an aquatic filter did not alter this characterisation of the system; the principal point, according to Dr Cole, was that the main flow is bypassed. 325 In cross-examination Dr Cole did not agree that there was uncertainty about what is shown in Figure 3 and, in particular, whether part of the air did not pass through the filter and the sensor or detector. He disagreed with the suggestion that the filter and the sensor or detector occupied the whole of the chamber. That suggestion was based on three features of Figure 3 and it is convenient to identify them at this stage. First, in Figure 3 there are no directional arrows showing the flow of air around the filter and the sensor or detector. There are directional arrows in other parts of Figure 3. Secondly, the written description of Figure 3 and indeed of the other Figures in the Nohmi patent contain no reference to a bypass arrangement. Thirdly, the fact that the words "air inlet" mean the inlet to the sampling chamber. I refer to the last sentence of the passage from the written description in the Nohmi patent set out in [322] above. 326 Mr Jawerth's evidence was similar in effect to that given by Dr Cole. He noted that the aspirator was located downstream of the secondary duct means but he did not think that fact was of any consequence. 327 Mr Johnson's evidence was also similar in effect to that given by Dr Cole. He considered that a significant proportion of the air passing through the chamber would bypass the filter and the sensor or the detector. He considered that the paper filter was designed to protect the detector by removing water droplets and other gross particles. The aquatic filter was designed to remove environmental impurities such as vapour, oil mists and dust. Mr Johnson disagreed with the suggestion, advanced in cross-examination, that the sampling chamber 17 represented a VESDA unit with or without a fan. 328 Mr Fox gave evidence to the effect that he assumed that the high-sensitivity light-scattering type smoke detector referred to in the Nohmi patent and shown in Figure 3 as being within chamber 17 was a VESDA unit because in 1990 or thereabouts, Nohmi Bosai were the exclusive distributors of VESDA units which it obtained from IEI (Aust). Mr Fox said that the VESDA unit was the only high-sensitivity, light-scattering type smoke detector with which Nohmi Bosai was involved. The significance of that fact (if it be the fact) is that the VESDA unit would occupy or be the whole of the sampling chamber (it was inconceivable it would be otherwise) and therefore no bypass arrangement would be involved. The suction pump shown in Figure 3 was to be explained on the basis that the fan in the VESDA unit would not be powerful enough to draw air through the aquatic filter. 329 Mr Barrett said that he considered the items shown in Figure 3 were not accurately represented in that figure. The drawing is purely schematic "so as to try to convey a very rough idea of how things are linked together". Mr Barrett said that he would not conclude from the Nohmi patent that a bypass arrangement was being suggested. He said that the emphasis in the Nohmi patent is on the aquatic filtering unit. 330 Mr Barrett agreed that his reliance in his oral evidence on the absence of arrows in the sampling chamber was not referred to in his affidavits and he agreed that the arrangement with the sampling chamber in Figure 3 in the Nohmi patent bore a striking resemblance to the arrangement shown in Figure 2 in the specification. 331 Mr Girling's evidence was similar in effect as that given by Mr Fox. 332 With some hesitation, I have reached the conclusion that it is not clear whether Figure 3 shows a bypass arrangement and therefore the Nohmi patent does not contain a clear and unmistakeable direction to construct an apparatus which embodies the features of the principal claims in the specification. I have reached that conclusion for a number of reasons none of which is decisive in itself. First, there is nothing in the written description of the Nohmi patent which refers to a bypass arrangement. As I have said, the chief feature of the invention is the aquatic filter. Secondly, the evidence is to the effect that an aquatic filter is a highly efficient form of filter and that tends to negate any suggestion that air needs to bypass the paper filter. Thirdly, there is the absence of directional arrows showing the air flowing around the filter and the sensor or detector. This is perhaps something of a negative factor. The presence of directional arrows would have made acceptance of the respondent's argument inevitable. Finally, I am unable to exclude the possibility that Figure 3 was drawn the way it was not to show a bypass arrangement, but rather to show in a clear way the components of the chamber. 333 For these reasons, the Nohmi patent is not an anticipation. I make it clear that in reaching this conclusion I have not relied on two other arguments put by the applicant. First, it was submitted that the chamber was likely to be a VESDA box which would not have included a bypass arrangement. I am unable to see that that conclusion follows from the fact that Nohmi Bosai was a distributor of VESDA E700s at about the time of the Nohmi patent. Secondly, I think the words, in the Nohmi patent: "…a paper filter F is provided at the air inlet for protecting the sensing section" are somewhat equivocal as to the location of the filter (that is, whether it is at the inlet to the chamber or the inlet to the sensor or detector) and do not point clearly to the filter being at the air inlet of the chamber.

Relevant legal principles 334 At the relevant time, s 18(1)(b)(ii) of the Act provided that a patentable invention is an invention that, so far as claimed in any claim: "(b) when compared with the prior art base as it existed before the priority date of that claim: … (ii) involves an inventive step;" 335 At the relevant time, s 7(2) and (3) of the Act were in the following terms: "(2) For the purposes of this Act, an invention is to be taken to involve an inventive step when compared with the prior art base unless the invention would have been obvious to a person skilled in the relevant art in the light of the common general knowledge as it existed in the patent area before the priority date of the relevant claim, whether that knowledge is considered separately or together with either of the kinds of information mentioned in subsection (3), each of which must be considered separately. (3) For the purposes of subsection (2), the kinds of information are: (a)prior art information made publicly available in a single document or through doing a single act; and (b)prior art information made publicly available in 2 or more related documents, or through doing 2 or more related acts, if the relationship between the documents or acts is such that a person skilled in the relevant art in the patent area would treat them as a single source of that information; being information that the skilled person mentioned in subsection (2) could, before the priority date of the relevant claim, be reasonably expected to have ascertained, understood and regarded as relevant to work in the relevant art in the patent area." 336 The Act does not contain a definition of "inventive step". I have set out above the definitions of "prior art base" and "prior art information" in the context of my discussion of the question of novelty (see [162] above). 337 The legal issues which must be addressed are the meaning of inventive step and obviousness, the attributes of the person skilled in the relevant art, the knowledge which is common general knowledge and the meaning of the phrase in s 7(3) of the Act, "be reasonably expected to have ascertained, understood and regarded as relevant to work in the relevant art in the patent area". In addition to these issues I will address the warnings against the misuse of hindsight and the use of secondary evidence such as the success of the invention and the failure of others to conceive of the invention. 338 The sections in the Act at the relevant time which dealt with inventive step (that is, ss 18(1)(b)(ii), 7(2), 7(3)) raised the threshold of inventiveness compared with the position as it was under the Patents Act 1952 (Cth). Nevertheless, case law which developed prior to the changes remained relevant: Lockwood Security Products Pty Ltd v Doric Products Pty Ltd [No 2] (2007) 235 CLR 173 ("Lockwood [No 2]") (at 190-195 [36]-[50]). 339 "Obvious" means very plain and the question of what is obvious is a question of fact (Aktiebolaget Hässle v Alphapharm Pty Limited (2002) 212 CLR 411 ("Alphapharm") at 427 [34]-[35], 443 [79]). There is no distinction between obviousness and lack of an inventive step (Lockwood [No 2] 195 [52]). A "scintilla of invention" remains sufficient in Australian law to support the validity of a patent (Woolworths Ltd v WB Davis & Son Ltd Inc (1942) 16 ALJ 57 at 59 per Williams J; Alphapharm at 431 [48]; Lockwood [No 2] at 195 [52]). 340 The question of obviousness is not to be confined to a "problem and solution" approach particularly with a combination patent (Alphapharm at 429 [40]). Ingenuity may lie in an idea for overcoming a practical difficulty in circumstances where a difficulty with a product consisting of a known set of integers is common general knowledge (Lockwood [No 2] 200-201 [65]). 341 The exercise which the Court is required to carry out in determining obviousness is to look forward from the prior art base to see what a person skilled in the art is likely to have done when faced with a similar problem which the patentee claims to have solved with the invention (Lockwood [No 2] at 218 [127]). 342 In The Wellcome Foundation Limited v VR Laboratories (Aust) Pty Ltd (1981) 148 CLR 262, Aickin J (with whom Gibbs ACJ, Stephen, Mason and Wilson JJ) agreed, said (at 286): "The test is whether the hypothetical addressee faced with the same problem would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not." 343 In Alphapharm, the High Court considered what Aickin J meant when he used the word "routine". The Court said (at 432-433 [51]-[53]): "51 What Aickin J had in mind as 'routine' appears from an earlier passage in his judgment in which he was discussing the question whether evidence of the steps taken by the patentee was relevant and therefore admissible in a revocation action. His Honour said [77] : 'Evidence of what he did by way of experiment may be another matter. It might show that the experiments devised for the purpose were part of an inventive step. Alternatively it might show that the experiments were of a routine character which the uninventive worker in the field would try as a matter of course. The latter could be relevant though not decisive in every case. It may be that the perception of the true nature of the problem was the inventive step which, once taken, revealed that straightforward experiments will provide the solution. It will always be necessary to distinguish between experiments leading to an invention and subsequent experiments for checking and testing the product or process the subject of the invention. The latter would not be material to obviousness but might be material to the question of utility.' (Emphasis added.) 52 There are distinct strands of thought in this passage which may now be considered in terms applicable to the issues in this ligitation. First, the working trials of which Dr Cederberg gave evidence may be (it is not necessary to determine the point) an example of the 'subsequent experiments for checking and testing', to which Aickin J referred at the end of the above passage. Secondly, the invention claimed in the Patent lay not in perceiving 'the true nature of the problem' to which 'straightforward experiments' then would provide the solution; the invention was in the interaction between the integers of the compound, to answer the known problem. Thirdly, in a case such as the present, the relevant question was that posed in the first part of the passage. Were the experiments 'part of' that inventive step claimed in the Patent or were they 'of a routine character' to be tried 'as a matter of course'? If the latter be attributable to the hypothetical addressee of the Patent, such a finding would support a holding of obviousness. 53 That way of approaching the matter has an affinity with the reformulation of the 'Cripps question' by Graham J in Olin Mathieson Chemical Corporation v Biorex Laboratories Ltd. This Court had been referred to Olin in the argument in Wellcome Foundation. Graham J had posed the question: 'Would the notional research group at the relevant date, in all the circumstances, which include a knowledge of all the relevant prior art and of the facts of the nature and success of chlorpromazine, directly be led as a matter of course to try the CF3 substitution in the "2" position in place of the -C1 atom in chlorpromazine or in any other body which, apart from the -CF3 substitution, has the other characteristics of the formula of claim 1, in the expectation that it might well produce a useful alternative to or better drug than chlorpromazine or a body useful for any other purpose?' (Emphasis added.)' That approach should be accepted." (Footnotes omitted.) 344 In Lockwood [No 2] the High Court said (at 198 [59]): "For the purposes of considering this Patent and its treatment in the Courts below, it is instructive to start with an old but frequently repeated description of the processes of invention by Fletcher Moulton [Fletcher Moulton, The Present Law and Practice Relating to Letters Patent for Inventions (1913), p 24 (footnotes omitted)]:

'An invention may, and usually does, involve three processes. Firstly, the definition of the problem to be solved or the difficulties to be overcome; secondly, the choice of the general principle to be applied in solving this problem or overcoming these difficulties; and thirdly, the choice of the particular means used. Merit in any one of these stages, or in the whole combined, may support the invention.'" 345 A person skilled in the relevant art is defined as a hypothetical, non-inventive worker in the relevant field of technology in Australia who is equipped with common general knowledge in the art: Lockwood [No 2] at 197 [56]. 346 Common general knowledge means: "… the background knowledge and experience which is available to all in the trade in considering the making of new products, or the making of improvements in old, and it must be treated as being used by an individual as a general body of knowledge." Minnesota Mining and Manufacturing Company v Beiersdorf (Australia) Limited (1980) 144 CLR 253 at 292 per Aickin J. 347 In Alphapharm Pty Ltd v H Lundbeck A/S (2008) 76 IPR 618 Lindgren J addressed the question of the circumstances in which information in a document is part of common general knowledge. He said (at 667) [221]: "As noted earlier, it was held in Astra that information recorded in a document, even a document widely circulated within the art, is not part of general common knowledge merely because the skilled addressee could be expected to locate it. The question is whether it is 'generally accepted without question' or 'generally regarded as a good basis for further action' by the bulk of those in the art: Minnesota Mining and Manufacturing Co v Tyco Electronics Pty Ltd (2002) 56 IPR 248 at [100], quoting Blanco White TA, Patents for Inventions and the Protection of Industrial Design (5th ed, Stephens, London, 1983) at [4-207]." 348 The word "ascertained" in s 7(3) simply means discovered or found out, and the word "understood" means that, having discovered the information, the skilled addressee would have comprehended it or appreciated its meaning or import (Lockwood [No 2] 219 at [132]). As to what the skilled person would regard as relevant to work in the relevant art, the High Court in Lockwood [No 2] said (at 223 [153]): "The question of what a person skilled in the relevant art would regard as relevant, when faced with the same problem as the patentee, is to be determined on the evidence. The starting point is the subject matter of the invention to be considered together with evidence in respect of prior art, common general knowledge, the way in which the invention is an advance in the art, and any related matters. It should be mentioned that the starting point is not necessarily the inventive step as claimed, or even agreed between parties, because the evidence, particularly in respect of a combination of integers, may support a different inventive step." 349 The authorities contain many warnings against the misuse of hindsight. In Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Limited (1980) 144 CLR 253, Aickin J said (at 293): "It is in relation to this process that the misuse of hindsight is most common. When once an idea or an object or a process or a combination, admittedly novel, has been published, it is very easy to say after perhaps months of search and study in the Patent Office and the public libraries that the integers into which the patent might be dissected could be found scattered amongst the prior documents by a person who already knew the solution to the problem and therefore knew what to look for and what to discard. But that process does not demonstrate lack of an inventive step. The opening of a safe is easy when the combination has been already provided." 350 In Alphapharm the Court said (at 423-424 [21]): "The defendant to an infringement action who cross-claims for revocation on the ground of obviousness bears the onus of establishing that case. This obliges the defendant to lead evidence looking back to the priority date, sometimes, as here, many years before trial. In those circumstances, the warnings in the authorities against the misuse of hindsight are not to be repeated as but prefatory averments and statements of trite law. The danger of such misuse will be particularly acute where what is claimed is a new and inventive combination for the interaction of integers, some or all of which are known. It is worth repeating what was said by Lord Diplock in Technograph Printed Circuits Ltd v Mills & Rockley (Electronics) Ltd:

'Once an invention has been made it is generally possible to postulate a combination of steps by which the inventor might have arrived at the invention that he claims in his specification if he started from something that was already known. But it is only because the invention has been made and has proved successful that it is possible to postulate from what starting point and by what particular combination of steps the inventor could have arrived at his invention. It may be that taken in isolation none of the steps which it is now possible to postulate, if taken in isolation, appears to call for any inventive ingenuity. It is improbable that this reconstruction a posteriori represents the mental process by which the inventor in fact arrived at his invention, but, even if it were, inventive ingenuity lay in perceiving that the final result which it was the object of the inventor to achieve was attainable from the particular starting point and in his selection of the particular combination of steps which would lead to that result.'" 351 In determining whether an invention is obvious in light of common general knowledge, secondary evidence is to be given such weight as the circumstances suggest is appropriate. Secondary evidence includes the commercial success of an invention, whether it satisfies a long-felt want or need, the failure of others to find a solution to the problem at hand and copying of the invention by others such as competitors. In Lockwood [No 2] the High Court said that an Australian court should be slow to ignore secondary evidence or to rely on its own assumed technical expertise to reach conclusions contrary to such evidence (at 216 [116]). The Court went on to say (at 216 [119]): "When skilled, non-inventive persons, and in this case also a skilled inventive person (Mr Garland), looking for improvements, fail to arrive at the invention, it is impossible to suggest that it would have been obvious to the skilled and not necessarily inventive person. The evidence supports the primary judge's findings."

The Tyco objection 352 Each of the witnesses who gave evidence at the trial had sworn affidavits before the trial and those affidavits had been filed and served upon the opposing party. In their affidavits a number of the respondent's witnesses had expressed an opinion on the issue of inventive step under s 7(2) and (3) of the Act. The applicant objected to those witnesses giving evidence on the question of inventive step and I was asked to rule that certain paragraphs were inadmissible. The applicant referred to the objection as the Tyco objection. That was a reference to the decision of the Full Court of this Court in Minnesota Mining and Manufacturing Co v Tyco Electronics Pty Ltd (2002) 56 IPR 248 ("Tyco Electronics"). I rejected the applicant's contention and I received the evidence. These are my reasons for doing so. 353 The relevant witnesses were Dr Cole, Mr Jawerth, Mr Johnson and Mr Piik-Wakeling. 354 The applicant's submission was that the evidence was "fundamentally flawed" because of the following matters: 1. Each of the witnesses was "tainted" by hindsight knowledge of the specification. In other words, they knew of the claims in the specification before giving their evidence on inventive step; and 2. Each of the witnesses had given evidence by way of a statutory declaration or affidavit on prior art for the purposes of the challenge to novelty before being asked to express an opinion on inventive step. 355 The applicant referred to the fact that the task of the Court in considering inventive step is to look "forward from the prior art base to see what a person skilled in the relevant art is likely to have done when faced with a similar problem which the patentee claims to have solved with the invention" (Lockwood [No 2] at 218 [127]). It also referred to the Court's warnings about the misuse of hindsight (Alphapharm at [21]). 356 In support of its objection, the applicant made particular reference to the decision of the Full Court of this Court in Tyco Electronics. In that case, the Full Court addressed the admissibility and (if admissible) the weight to be given to evidence of experts about inventive step, particularly where, prior to forming their opinion, those experts were provided with the patent or patent application. The Court said (at 258-259 [45], [46], [48], [49], [50]): "The manner in which the evidence of some of the experts in the present case was bought into existence suggests that relatively little weight should be given to certain of that evidence. For example, witnesses were provided with a copy of the patent. They were either provided with a large number of other documents or found them in response to the task that was set them. That is hardly calculated to result in objective evidence as to what the hypothetical uninventive but skilled worker would have done. To give the patent to a prospective witness is tantamount to leading the witness. Further, unless the other documents were part of the common general knowledge in Australia before the priority date, they are not relevant to any question of obviousness.

Evidence by 'experts' on the question of obviousness it is not always likely to be helpful: see Firebelt Pty Ltd v Brambles Australia Ltd(2002) 188 ALR 280; 54 IPR 449 at [46]. Indeed, where evidence is obtained in circumstances such as just described, the evidence is not likely to be helpful at all. …

Whether a claimed invention would have been obvious and did not involve an inventive step is probably an ultimate issue in a patent revocation proceeding. It is dubious whether that matter would be a fact in issue. However, assuming that an opinion as to whether a claimed invention would have been obvious and did not involve an inventive step is within s 80 of the Evidence Act, it is still necessary to satisfy s 79 in order to exclude the opinion rule.

Most expert witnesses called in patent cases before the court have specialised knowledge based on training, study or experience. However, an opinion as to whether a claimed invention was obvious will not be based solely on such specialised knowledge. It will also be based on an understanding of patent law. Questions of obviousness and inventive step involve questions of law or questions of mixed fact and law. Such experts will not necessarily have a detailed understanding of the intricacies of patent law and, indeed, may have no particular knowledge of that field at all. A significant difficulty for the operation of s 80, therefore, will be to determine the understanding of the law of the prospective witness.

Questions of obviousness and inventive step are ultimately for the court to determine, irrespective of the opinion expressed by any number of experts. Evidence by an expert as to whether a claimed invention was obvious or did not involve an inventive step will of necessity be essentially argumentative. Even if admissible, such evidence is likely to result in a waste of time by reason of the analysis of and cross-examination of the evidence that will be required. Such evidence is therefore a prime candidate for the application of s 135 of the Evidence Act, under which the court may refuse to admit evidence if its probative value is substantially outweighed by the danger that the evidence might be misleading or confusing or cause or result in an undue waste of time. Hence such evidence, even if it is strictly admissible, is unlikely to be helpful and it is preferable to exclude it." 357 As I understood the applicant's submission, it did not suggest that the evidence to which it took objection was not relevant. If evidence is relevant then it is admissible unless a provision in the Evidence Act 1995 (Cth) provides otherwise (s 56). Nor did the applicant suggest that I should refuse to admit the evidence in the exercise of the general discretion to exclude evidence under s 135 of the Evidence Act 1995 (Cth). 358 In those circumstances, it seemed to me that the issue was essentially one of the weight to be accorded to the evidence. In other words, the evidence was admissible, but the matters identified by the applicant were relevant to the weight to be accorded to the evidence. Ultimately, it is open to me not to accept the evidence of one or more of the relevant witnesses for the reasons identified by the applicant. That was the approach taken by the trial judge in Esco Corporation v PAC Mining Pty Ltd [2008] FCA 640; (2008) 76 IPR 191 and upheld on appeal: PAC Mining Pty Ltd v Esco Corporation [2009] FCAFC 18 at [80]; (2009) 80 IPR 1. 359 It was for these reasons that I rejected the applicant's objection to the evidence.

The problem and the invention 360 The problem addressed by the invention was the problem of filter-clogging. For many years before the priority date smoke detection systems had included filters to protect the detectors and to minimise the possibility of false alarms. The filters would become clogged over time and would need to be replaced or cleaned. How quickly the filter became clogged depended on the nature of the filter and the type of environment in which it was operating. For example, filters operating in the London Underground, where there was considerable brake block dust from the train operations, needed to be changed quite frequently. I doubt whether there is a need for evidence on such an obvious point, but I note that the need to change the filter because it gradually becomes dirty was referred to by Dr Cole in 1983 in a document which formed part of the applications manual for the VESDA E 700 units. 361 The filter-clogging problem became more acute in 1991 and 1992. From about 1991 Mr Fox received reports of cases where a VESDA detector which was working at the time of installation later became incapable of operating effectively. That occurred in a British Telecom exchange building in central Birmingham, United Kingdom. The report was that a relay coil burnt out, producing a large volume of smoke and that that smoke was not detected by the VESDA smoke detection system. 362 In 1992, a particular problem involving the filter arose. In the evidence it was called the Spanish problem. It seems that the distributor for IEI either (Aust) or (UK) in Spain reported that filters which looked clean were not operating effectively. IEI (UK) carried out tests on such filters and discovered that although a filter might look clean, nevertheless smoke could not pass through it freely. Furthermore, a filter might not be effective even where there was no appreciable pressure drop across the filter. Mr Fox reported the Spanish problem to Dr Cole. IEI (UK) undertook a research programme to see whether the filter‑clogging problem could be solved and IEI (Aust) and Dr Cole undertook a similar programme. 363 The description of the filter-clogging problem in the specification of the Patent application is as follows: "In order to prevent the internal parts of a transducer from becoming contaminated, an air filter is employed to remove larger particles than anticipated with products of overheating materials. The performance and renewal of this filter, with known aspirating detectors, is often a problem in maintaining a consistent performance by a detector. The problem arises in that, as the air filter becomes increasingly contaminated through usage, the effective pore size of filter medium becomes increasingly smaller. This effect is sometimes known as 'tea leafing' because of the similarity with the effect of tea leaves hindering passage of tea when a tea strainer is used. The effect on conventional aspirating smoke detectors is that the sensitivity of the detector decays with time as the filter becomes increasingly blocked, leaving the system in some cases significantly less sensitive after only a few months of use." 364 In its closing written submissions, the applicant described the essence of the invention as: "… the realisation of the applicability of a bypass as a means of substantially ameliorating or practically eliminating, the problem of filter contamination or filter clogging as had occurred in the art of aspirating smoke detectors and as had been specifically presented by the problem described as the 'Spanish problem'." 365 In its closing written submissions, the respondent described the invention as embodying a simple bypass in its broadest conception and it described that as: "[T]he incorporation of a particles filter upstream of the detector in a secondary duct so that only a part of the air stream in the main flow is passed through the filter to the detector." 366 I do not think there is any material difference between the two descriptions; the first focuses on the idea, whereas the second focuses on the arrangement of the parts of the system.

The respondent's case 367 The respondent's case is that the invention did not involve an inventive step because the invention would have been obvious to a person skilled in the relevant art: 1. in the light of the common general knowledge as it existed in Australia before 30 July 1993; or 2. in the light of the common general knowledge as it existed in Australia before 30 July 1993 and the information in an article written by Messrs J Brown, N Moores and C Birkby entitled "The early detection of fires in coal pulverising mills by measurement of carbon monoxide", being an article which met the requirements of s 7(3) of the Act ("the Brown, Moores and Birkby article").

Inventive step in light of common general knowledge as it existed in Australia before 30 July 1993 368 The evidence before me may be seen as falling into one of three categories although there is an overlap between the second and third categories. The first category was evidence which, for the most part, was not in dispute, about the smoke detection industry in Australia before the priority date. 369 The second category was evidence from various witnesses called by the respondent to the effect that before the priority date they would have considered a bypass arrangement to be an obvious step. That evidence was strongly challenged by the applicant who said that no weight should be placed on it for two reasons. First, the evidence involved a misuse of hindsight, especially in circumstances where the witnesses had seen the specification, some prior art and the Brown, Moores and Birkby article before considering the question of inventive step. Secondly, the applicant submitted that the evidence was not credible in light of the fact that the witnesses themselves had not conceived the idea of a bypass arrangement. 370 The third category was what has been called secondary evidence being evidence concerning the alleged success of the invention, the failure of others to conceive of the idea of a bypass arrangement and alleged copying of the invention by the respondent. 371 I start with the first category of evidence. 372 At the priority date the VESDA E700 Mk I, Mk II and Mk III units were widely published and used in Australia and their features and use formed part of the common general knowledge in Australia. Each unit was used either in conjunction with air-conditioning ducts or with a dedicated network of sampling pipes. The Mk II and Mk III units consisted of a detector enclosure, a filter (in the case of the Mk II unit a short time after it was introduced), a fan and an E700 VESDA detector. The filter was placed upstream of the detector. 373 Dr Cole gave evidence which I accept about the use of the VESDA E700 units in association with air-conditioning ducts. Dr Cole said that before the priority date about fifty VESDA E700 Mk I units were installed in air-conditioning ductwork, including a VESDA E700 Mk I unit at the Channel 2 transmission towers on Mt Dandenong, Victoria, and at Loy Yang Power Station, Victoria. A number of VESDA E700 Mk II units were installed in air-conditioning duct work, including at the Regent Hotel (now Hotel Sofitel), Collins Place, Melbourne, Newport Power Station, Victoria, and the Melbourne Remand Centre. Something in the order of 1,000 units had been installed in association with air-conditioning ducts. IEI (Aust) distributed many copies of brochures which showed the use of its VESDA E700 units in association with air-conditioning ducts. 374 Dr Cole also gave evidence which I accept that the dedicated sampling pipes were standard plastic electrical or plumbing pipes and that the VESDA E700 series was marketed and used in conjunction with a dedicated network of sampling pipes. At least half of the installations of the VESDA E700 units involved the use of dedicated sampling pipes. 375 At the priority date, the Olsen D51B smoke detector and its use with air-conditioning ducts was well known in Australia and was part of common general knowledge in Australia. It was known that the Olsen D51B smoke detector included an inlet probe which entered the enclosure in which there was a filter, a single detector and an outlet probe. 376 There were smoke detection units other than the Olsen D51B unit which were used in association with air-conditioning ducts. Those units were as follows: (a) the Hochiki SDB A-100 smoke detector duct probe; (b) the Apollo air sampling unit or duct probe; (c) the BRK DH 1851/2851 series duct detector; (d) the Cerberus FPK 90 series duct detector; (e) the Nittam detector and duct probe; and (f) the duct sampling unit made by FFE UK. 377 At the priority date it was clear from the sales material, including the brochures, that the VESDA E700 units could be used in association with air-conditioning ducts or a dedicated network of sampling pipes. A dedicated network of sampling pipes was an additional cost which could be avoided by using existing air-conditioning ducts. On the other hand, a dedicated network of sampling pipes would be used if there were no air-conditioning ducts and could be used if the air-conditioning might be turned off, or if there was a possibility of a power failure, or if there was particularly valuable equipment to be protected. At the priority date, it was common general knowledge that whether the systems were used with one or the other was a design choice which depended on a number of well-known considerations. 378 Mr Jawerth and Mr Johnson gave evidence that there was a time in Australia, which they identified as the 1960s and 1970s, when point type detectors with filters or other devices were placed inside air-conditioning ducts. This practice proved ineffective either because the filters were ineffective and the detectors or sensors were affected or because the filters clogged. Eventually, the Commonwealth Government issued a directive that point type detectors were not to be placed in air-conditioning ducts in Commonwealth Government building projects. This led to the use, or the increasing use, of duct sampling units such as the Olsen D51B. It was understood in the industry that these units took a sample of air from an air-conditioning duct, thereby eliminating or at least reducing the problems caused by placing point type detectors in air-conditioning ducts. To this extent, the principle of taking a sample of air for smoke detection analysis was well known in the smoke detection industry before the priority date. I accept the evidence of Mr Jawerth and Mr Johnson with respect to these matters. 379 I turn now to the second and third categories of evidence. I will deal with them together, as they overlap. 380 Mr Fox said that he was the one who conceived the idea of a bypass arrangement and that it was embodied in the design of the Stratos-HSSD smoke detection system. Mr Fox said that the idea occurred to him when he and a friend were working on a motor vehicle and he noticed that there was a "wastegate" attached to a turbocharger which "dumped" a substantial proportion of air entering the intake manifold. 381 A number of witnesses said to be skilled in the art at the priority date gave evidence which was relevant to the question of inventive step. For the respondent, there was evidence from Dr Cole, Mr Jawerth, Mr Johnson, Mr Piik-Wakeling, Mr Verzjil and, to a limited extent, Mr Petersen and Mr Miles. For the applicant, there was evidence from Mr Fox, Mr Barrett and Mr Bray. Mr Fox did not work in the industry in Australia and that must be taken into account. 382 The applicant submits that I should place no weight on the evidence given by Mr Knox or Mr Mitchell with respect to inventive step. Mr Knox was called by the respondent. He arrived in Australia in August 1993 and he started work with IEI (Aust) in October 1993. It appears that he had no personal knowledge of the relevant industry before 30 July 1993. He was probably in a position to infer certain things from documents and products he saw after commencing employment with IEI (Aust), but I am disposed to place no weight on his evidence on inventive step, bearing in mind that I have a good deal of direct evidence of the relevant industry before the priority date. I take the same approach to Mr Mitchell's evidence because at all relevant times, he has been resident in the United Kingdom. 383 It is convenient to start with the respondent's witnesses. 384 There was in effect a preliminary point taken by the applicant. It was that I should disregard the evidence of the respondent's witnesses about inventive step because before they addressed the issue of inventive step they had seen the specification, some prior art and the Brown, Moores and Birkby article. This submission was put in the alternative to the Tyco objection in that it was put that even if the evidence was admissible it was of so little weight that it ought to be disregarded. 385 It is the case that Dr Cole, Mr Jawerth, Mr Johnson and Mr Piik-Wakeling had seen the specification, some prior art and the Brown, Moores and Birkby article before they addressed the issue of inventive step. 386 I refer to the passage from Tyco set out above (at [356]). Dr Cole, Mr Jawerth, Mr Johnson and Mr Piik-Wakeling gave evidence as to developments in the industry before the priority date. That is a matter of fact and it is open to me to accept and act on that evidence. Each of them also gave evidence as to what they would have seen as potential solutions before the priority date to the problem which is said to be solved by the invention and the advantages of each solution. Expressed in that way the question is a hypothetical one. It seems to me that providing they have appropriate knowledge there is no reason why they cannot give evidence on that topic and if I find their evidence cogent and persuasive there is no reason I cannot act on it. In assessing their evidence I will take into account the fact that each of them had, prior to expressing their opinion, seen the specification and some prior art. 387 Dr Cole, Mr Jawerth, Mr Johnson and Mr Piik-Wakeling also gave evidence on whether the bypass arrangement was obvious before the priority date having regard to common general knowledge in the smoke detection industry. That is a matter of opinion. It seems to me that there is a good deal more force in the applicant's challenge to this evidence. As the Full Court said in Tyco Electronics, an opinion as to whether a claimed invention is obvious will be based not only on specialised knowledge but also on an understanding of patent law. In this case, there was no exploration in the evidence of each witness of his understanding of the meaning of the word "obvious". In those circumstances and because the witnesses had seen the specification before expressing their respective opinions on obviousness I place no weight on those opinions. 388 The other substantial attack on the evidence of at least Dr Cole, Mr Jawerth and Mr Johnson was that each of them had in fact faced the filter-clogging problem before the priority date and none had found the solution of a bypass arrangement. In those circumstances it was submitted that their evidence about inventive step could not be relied upon. The applicant went further in the case of Dr Cole and submitted that he was not a credible witness on the topic of solving the filter-clogging problem. 389 The evidence that these witnesses had looked for a solution to the filter-clogging problem but did not discover the bypass arrangement had a further significance according to the applicant. It was said to be powerful secondary evidence, particularly in the case of Dr Cole (who was an inventive skilled worker) of the type of evidence identified by the High Court in Lockwood [No 2] (see [351] above). 390 I will address this attack and the availability of secondary evidence in the context of addressing the evidence of the witnesses. 391 There is no doubt that Dr Cole was skilled in the relevant industry before the priority date. In fact, as I have said I think he must be considered an inventive person in the field. Over the years, a number of patent applications have been made naming Dr Cole as the inventor. Dr Cole is an expert in fluid dynamics. I have already referred to his academic qualifications and practical experience. 392 Dr Cole gave evidence that in his opinion it was obvious to combine features of an E700 smoke detection system including taking a sample of air from dedicated sampling pipes and putting only that sample through the particles filter and the detector. For reasons I have given I place no weight on his conclusion of obviousness. 393 Dr Cole said that he considered the idea of a bypass arrangement before July 1993 but that he rejected the idea. He was strongly challenged on that point by the applicant. It is necessary to consider how his evidence emerged. 394 In his affidavit affirmed on 4 August 2006 Dr Cole said that he and others at IEI (Aust) considered a bypass arrangement for use in the VESDA E700 Mk III. He said that the idea was rejected for two reasons, being a "plumbing difficulty" and a concern that a bypass would lead to a fouling of the new aspirator. Maintaining a filter in the main duct prevented the narrow channels of the new high performance aspirator that Dr Cole had developed by 1990 being clogged with fibrous material. It was a matter of balancing the benefit of not fouling the aspirator against the "known benefit" (as Dr Cole described it) of having a bypass. In his affidavit affirmed on 13 December 2007, Dr Cole said that: "Consideration and discussion of issues such as the bypass arrangement were dealt with by me, Simon Price and Mr Verzijl." 395 Dr Cole was cross-examined about his research activities in response to the Spanish problem. He said that Mr Barrett and Mr Bray were employees at IEI (Aust) at the time and that they were assigned to work on a flow monitoring activity. Dr Cole agreed that he considered a vortex solution and a labyrinth. When asked about the bypass arrangement which he claimed he had considered, he said he had "a model of it somewhere". 396 Mr Verzijl made a statutory declaration in the opposition proceedings on 26 March 2008, and he gave evidence at the trial. In fact, he was interposed during the cross-examination of Dr Cole and it is convenient to deal with his evidence at this point. Mr Verzijl was an honest witness and there was no challenge to his evidence. 397 Mr Verzijl is a mechanical engineer. In the late 1980s and early 1990s he operated his own mechanical engineering business through a company called Verzijl Engineering Pty Ltd. That business specialised in product development. 398 In about 1991, Mr Verzijl worked with Dr Cole on a number of projects involving the VESDA smoke detection system. The projects included work to prolong the battery life of the system and work to improve the filter including, in relation to the filter, improving the ability of the filter to capture more contaminants without clogging. 399 Mr Verzijl and Dr Cole carried out experiments with a paper filter and a foam cartridge filter. In essence, the tests were designed to determine whether, in terms of performance, a foam filter was superior to a paper filter. In the result, a foam filter was considered a better filter and in about the middle of 1993 it was incorporated into the VESDA E700 units. Mr Verzijl's company supplied the foam filters to IEI (Aust), then to the respondent and now he supplies them to Xtralis. 400 Mr Verzijl made no reference in his evidence to a bypass arrangement or to discussing a bypass arrangement with Dr Cole. 401 I pause at this point to say that in 1992 Dr Cole was involved in research and development and that the Research and Development department of IEI (Aust) consisted of Mr Simon Price, who was Research and Development Manager, Mr Chris Price, Mr Barrett, Mr Michael Brodie and Mr Bray. 402 When cross-examination of Dr Cole resumed after Mr Verzijl had given his evidence, Dr Cole was asked about persons with whom he had discussed the bypass arrangement. He said that he did discuss that topic with Mr Simon Price but he could not recall discussing the topic with Mr Verzijl. 403 Dr Cole's explanation for not mentioning the model before was as follows: "Well, I have - I don't want to sound critical of any of the - the people involved, but I have mentioned the - some of these things before and they have not been taken up. I mean, I am just here to give, I thought, expert evidence. And that's all." 404 In re-examination, Dr Cole drew a diagram of the bypass arrangement he considered in 1992 or 1993 (exhibit R28) and he identified a model that he had constructed (exhibit R29). 405 The applicant applied for leave to reopen its cross-examination of Dr Cole in order to question him about the drawing and the model. I considered that in the circumstances leave should be granted. Dr Cole was cross-examined about the model. He said that the model was essentially a VESDA scanner valve with the electrical connections associated with it, an E700 detector and a filter cartridge in a cylindrical form inside a transparent device in the shape of a flowerpot. The filter cartridge did not occupy the whole of the transparent device. He agreed that the model was not an operational model. He accepted that the whole model was not a model constructed in 1992. It was in fact a reconstruction. He said that when referring to the model he was really referring to the short piece of pipe which was to run from the filter to the pipe between the detector and the aspirator. 406 Dr Cole explained what he had done: "Sir, it's my understanding that the process I went through by obtaining this - resurrecting, if you will, this pipe and putting it back into the original position that was proposed in an earlier unit back in 1992, constitutes a reconstruction." 407 I was left with the impression in re-examination that the model produced was the model constructed before the priority date and it is unfortunate that the true position with respect to the model was not made clear on the occasion it was first produced. 408 I should mention at this point the evidence of Mr Barrett. It bears on whether I accept the evidence of Dr Cole about considering a bypass arrangement as a solution to the filter-clogging problem. Mr Barrett was an honest and straightforward witness. 409 In a statutory declaration made by Mr Barrett on 27 September 1999 and filed in the opposition proceedings, he said that during the time he was employed in the Research and Development department of IEI (Aust) there was never any discussion when he was present about a bypass arrangement. In a later statutory declaration made on 25 July 2001 he referred to the fact that he was involved in work on an accurate flow monitoring device and that he was aware of alternative filters being tested including a labyrinthine filter and an electrostatic filter. In a later affidavit sworn on 31 July 2009, Mr Barrett confirmed that neither Dr Cole nor a Mr Chris Price ever mentioned to him a bypass arrangement as a possible solution to the filter-clogging problem. Mr Barrett said that Mr Price was another engineer employed in the Research and Development department of IEI (Aust). He worked solely on research and development in relation to the VESDA products. 410 I should also mention at this point the evidence of Mr Bray. He is a consultant software engineer. He does not hold tertiary qualifications in mechanical engineering or fluid dynamics. His principal expertise is in the design and writing of software. He was employed by IEI (Aust) from about 1980 to April 1993. When Mr Bray started with IEI (Aust) he worked on the production line. In about 1984 he became part of the Research and Development department and he was a technician in that section. In about 1992 Mr Bray was involved in the redesign of the VESDA E700 Mk II detector. He said that the E700 Mk III was the result of the redesign work. Mr Bray said at one point that he was aware that customers of IEI (Aust) complained of filter-clogging problems. The only solution he could think of for the filter-clogging problem (putting himself back in the position he held in July 1993) was to replace the filters. When he was tested in cross-examination about his opinion he said he was not involved in providing solutions for a filter-clogging problem because up to the point he left IEI (Aust) filter-clogging was not a problem. Mr Bray was an honest witness but I do not think his evidence advances the matter. 411 I have considered carefully whether I should accept Dr Cole's evidence that in 1992 he considered but rejected a bypass arrangement as a solution to the filter-clogging problem. I think Dr Cole did consider a bypass arrangement in 1992 but that he quickly dismissed the idea. I have taken into account that there is no evidence which corroborates Dr Cole's evidence. The one piece of evidence that was produced as independent corroboration, that is to say, the model, turned out to be a reconstruction. I also take into account the fact that Mr Simon Price was not called to give evidence and Mr Verzijl gave no evidence of discussing a bypass arrangement with Dr Cole. These facts, and the absence of diary entries, and the fact that neither Mr Barrett nor Mr Bray had heard of a bypass arrangement suggest that Dr Cole gave the idea of a bypass arrangement fairly short consideration. Although, as I have said, it is unfortunate that the position with the model was not made clear at the outset, I am satisfied having regard to all of Dr Cole's evidence and the other evidence in the case, that he made a mistake about the model and he was not trying to mislead me. I accept that Dr Cole rejected the bypass arrangement for what he considered to be good reasons and I reject the suggestion that his reasons are illogical in view of other work being carried out at the time. 412 There is a second challenge to Dr Cole's evidence about the consideration he gave to a bypass arrangement. It is said by the applicant that the bypass arrangement Dr Cole gave evidence about did not involve part of the air which entered the system bypassing the filter. I do not accept that contention. Dr Cole's drawing shows air bypassing the filter and entering a short pipe which is connected to a pipe passing from the detector to the aspirator. I am satisfied that the bypass arrangement Dr Cole said he considered did in fact involve a stream of air bypassing the filter. 413 Before leaving Dr Cole's evidence concerning inventive step I note that in 1995, and after the respondent had acquired IEI (Aust), it launched a new product called a VESDA LaserPlus. That product incorporated a bypass arrangement. However, there are some differences between it and the bypass arrangement referred to in the specification. On 30 October 1996, Dr Cole presented a paper to the Fire Australia 1996 Convention at the Melbourne Exhibition Centre. The title of the paper was "Aspirated Smoke Detection Flexibility for Performance Based Building Codes". In the paper Dr Cole refers to the advantages of a bypass arrangement. I will return to the significance of this and the features of the VESDA LaserPlus later in these reasons. 414 In his affidavit sworn in May 2009, Mr Johnson said that, if confronted with a filter‑clogging problem in July 1993, he would have been aware of three broad approaches to the problem. The first approach was to take the smallest possible representative sample of air through the filter and thereby reduce the contaminants passing through the filter. The second approach was to slow down the airstream and thereby slow down the rate of airflow through the filter causing the larger particles to drop out of the airstream. The third approach was to devise or implement a self-cleaning filter. 415 Mr Johnson said a self-cleaning filter would increase the cost and complexity of installation. He said that the obvious solution was "to maintain a fast flow of air from the protected area, and take only a small sample of the air into a small channel, with the filter and detector within this smaller channel". Mr Johnson said the most cost-effective solution would have been to modify an existing system such as an E700 range rather than commencing a completely new development. 416 Mr Johnson said that he was aware of a filter-clogging problem in the 1980s. A report or survey on the problem was done by a member of Mr Johnson's staff. Mr Johnson recalled writing a report in relation to a small number of installations where there were problems with IEI VESDA smoke detection systems. 417 The applicant submits that I should reject Mr Johnson's evidence about what he considered to be the obvious solution to the filter-clogging problem because Mr Johnson himself was confronted with a filter-clogging problem in the 1980s and yet he did not conceive of the idea of a bypass arrangement as the solution. Furthermore, the fact that Mr Johnson had not concluded that a bypass arrangement was the solution to the filter-clogging problem was important secondary evidence supporting the conclusion that the bypass arrangement was not obvious. 418 I do not think the fact that Mr Johnson did not think of a bypass arrangement is significant. I say that because I do not think the evidence rises to the level suggested by the applicant. Mr Johnson gave evidence, which I accept, that the filter-clogging problem was not a major problem when SSL and Mr Johnson examined it and that SSL did not see their role as one of providing solutions. 419 Mr Johnson is very experienced in the field of fire and smoke detection. He gave his evidence in a careful and measured fashion. He was both credible and reliable. I accept Mr Johnson's evidence as to what he would have considered to be the solutions to the filter-clogging problem in July 1993. I also accept his evidence that a self-cleaning filter would increase the cost and complexity of installation. 420 For the reasons I have given, I place no weight on Mr Johnson's conclusion of obviousness. 421 In his affidavit sworn in May 2009, Mr Jawerth said that if he was facing a filter-clogging problem in July 1993 he would know of two obvious and well-known approaches to solving the problem. The first approach was to alter the filter medium or filter style. The second approach was to reduce the flow of air through the filter. Mr Jawerth said that the concept of taking a sample of air was well known in the industry in July 1993. The Olsen D51B was one of a number of sampling smoke detection systems available before 1993. Mr Jawerth said that altering the filter media or mechanism was a process which would have taken considerable time. He said that he knew from his experience with duct detection units, and in particular the Olsen D51B, that taking a smaller sample of air from a main flow, and only filtering that smaller sample, would prolong filter life and would effectively address the filter-clogging problem. He described the implementation of such a subsampling system as "trivial essentially only involving the creation of a secondary duct". 422 Mr Jawerth agreed that faced with a filter-clogging problem his company experimented with different types of filter and eventually came up with something which was acceptable, namely, the foam filter. 423 The applicant asked me to reject Mr Jawerth's evidence on similar grounds to those advanced in the case of Mr Johnson (see [417]). I do not think the fact that Mr Jawerth did not think of the bypass arrangement is significant. Mr Jawerth and the company for which he worked solved their filter-clogging problem by the introduction of a foam filter. 424 Mr Jawerth is very experienced in the field of fire and smoke detection. Like Mr Johnson, he gave his evidence in a careful and measured fashion. He also was both credible and reliable. 425 I accept Mr Jawerth's evidence as to what he would have considered to be solutions to the filter-clogging problem in July 1993. I also accept his evidence that altering the filter media or mechanism was a process that would have taken considerable time. 426 For the reasons I have given, I place no weight on Mr Jawerth's conclusion of obviousness. 427 In his affidavit sworn in May 2009, Mr Piik-Wakeling said that if he had been confronted with a filter-clogging problem in July 1993, he would have considered as general solutions to the problem altering the filter medium to prolong the filter life or altering the method of sampling to avoid drawing in large amounts of contaminant across the filter. Mr Piik-Wakeling said that the first alternative would have involved significant amounts of research or experimentation to identify an appropriate filter medium. 428 Mr Piik-Wakeling said that there were already "mechanisms" for implementing the second alternative. The first was to use a reverse pitot tube and the second was to adopt the principle of subsampling which was well known in the fire detection industry before July 1993. Mr Piik-Wakeling expressed the opinion that it would have been an obvious solution to the filter-clogging problem to take a smaller sample of a sample of air drawn from the protected space, and pass that smaller sample across the filter and detector. He said that in developing a smoke detection system to address a filter-clogging problem in July 1993 it would have been an obvious choice and no ingenuity would have been involved in combining the well-known components of the E700 including the fan, a single tubular detection chamber, a particles filter and a sampling pipe with the well-known subsampling concept and a network of sampling pipes. 429 Mr Piik-Wakeling is experienced in the field of fire or smoke detection. He also gave his evidence in a careful and measured fashion. He too was both credible and reliable. 430 I accept Mr Piik-Wakeling's evidence as to the solutions to the filter-clogging problem in July 1993. I also accept his evidence that altering the filter medium would have involved significant amounts of research or experimentation to identify the appropriate filter medium. 431 As with Mr Johnson and Mr Jawerth, I place no weight on Mr Piik-Wakeling's conclusion of obviousness. 432 The applicant referred to the evidence of Mr Barrett and Mr Bray. I have already referred to certain aspects of their evidence (at [408]-[410]). Mr Barrett said that a bypass arrangement never occurred to him while he was employed in the Research and Development department of IEI (Aust). 433 As I have said, the applicant also relied on what has been referred to as secondary evidence. For the reasons I have already given, I reject the suggestion that Dr Cole did not think of a bypass arrangement and I reject the suggestion that the fact that Mr Jawerth and Mr Johnson did not think of a bypass arrangement is significant. The applicant relied on two other forms of secondary evidence. First, it submitted that it is significant that the respondent included a bypass arrangement in its VESDA LaserPlus product which it released into the market in 1995. Secondly, it submitted that it is significant that its Stratos-HSSD smoke detection system which embodied its invention, was commercially successful. The facts relevant to these submissions follow. 434 First, shortly after IEI (Aust) was taken over by the respondent in 1995 a large team of employees was involved in the production of a new smoke detection system. The VESDA LaserPlus smoke detection system was the result and among other things it embodied a bypass arrangement. 435 In his paper (see [413] above) delivered on 30 October 1996 Dr Cole said the following: "A smoke detector that requires minimal maintenance has obvious advantages in such situations. There have been two main elements of the VESDA detector requiring routine maintenance.

The other main element was the dust filter, which loads up with dust particles at a rate that depends upon the environment, generally requiring replacement or cleaning of the filter about every two to four years.

In a given environment, the key factor that determines filter life is the sheer quantity of dusty air passing through the filter. To achieve a satisfactory smoke transport time within pipework (without resorting to very small tubing and a costly, unreliable and power-hungry vacuum pump), a significantly large airflow is required (in the vicinity of 40-140 litres/minute). This is achieved using the award-winning, highly efficient, specially designed VESDA aspirator. This has recently been modified to achieve a 6dBA sound level reduction and provided with a tachometer for accurate system flow control.

However, it is not necessary to pass all of this air through the detector. A representative sample of that air would have the same smoke density as the total flow. Consequently only a small percentage of the total flow needs to be filtered and passed through the detector chamber. This considerably increases the filter life and indeed, permits it miniaturisation.

This filter is effective in reducing the likelihood of false alarms caused by dust. However, to enable smoke detection, the filter does not remove particles of every size from the airstream, so there would remain a possibility of soiling the detector in the long term. Therefore a second stage, HEPA (high efficiency particle arrester) filter has been incorporated. This filter removes smoke as well as any remnant dust, producing a supply of clean air. This clean air is used to provide a fluid barrier or curtain covering all of the sensitive optical components within the detector chamber, preventing particles from settling on those components. Testing indicates that this should prevent soiling within a maintenance cycle of ten years." 436 Secondly, the applicant, or more accurately, its predecessor, Airsense Technology, developed the Stratos-HSSD system in the first half of 1993. It had a number of features including a system of artificial intelligence. This related to simplifying or automating the system. Other features of the product were a semiconductor laser as a light source which improved the reliability of the light source and the bypass arrangement so that only a small proportion of the air in the smoke detection system flowed for detection through the filter and detector, rather than the whole stream of air as in the then existing VESDA systems. This feature was designed to produce a product that would ensure consistent protection of the area to be protected, irrespective of the dust filter condition. The inventors were awarded the only Queen's Award for Technological Achievement ever presented for a fire detection or fire alarm product. That was for the technological advances incorporated in the Stratos-HSSD system. 437 Many thousands of Stratos-HSSD systems have been sold worldwide. 438 As to the development of the VESDA LaserPlus, Dr Cole said that in designing that system he did not copy the bypass arrangement from the Stratos-HSSD system. He pointed to a number of differences between the VESDA LaserPlus and the Stratos-HSSD system. Those differences were that the VESDA LaserPlus involved a branching out rather than a coaxial arrangement, the aspirator is between the outlet and inlet probe rather than upstream of the bypass and there are two flow regimes involving a fine filter and a coarse filter. I accept Dr Cole's evidence that he did not copy the bypass arrangement from the Stratos-HSSD system. 439 As to the second matter, I am prepared to find that the Stratos-HSSD smoke detection system has been a success. However, there are any number of reasons why the Stratos-HSSD smoke detection system has been a commercial success ranging from good marketing to features other than the bypass arrangement. I do not think the commercial success of the Stratos-HSSD system is a matter on which I can put a great deal of weight. 440 The invention was not directed to a new type of filter. Claims 1 and 3 refer to a "particles filter" and claims 4 and 6 refer to a particles filter designed and employed to remove larger particles than those intended to be detected. The use of filters in smoke detection systems in order to protect the detector was well known in the industry before the priority date. The Olsen D51B had a foam filter and the VESDA E700 Mk II was sold with a filter not that long after it was introduced into the market. In 1993 IEI (Aust) developed and introduced a new, open cell foam filter for the VESDA E700 Mk III. I have no doubt that it was well understood in the industry before the priority date that there were advantages and disadvantages associated with the use of a fine filter on the one hand or with the use of a coarse filter on the other. A fine filter would reduce the number of unwanted contaminants travelling to the detector but it might become dirty quite quickly. A coarse filter would not clog as easily but a number of unwanted contaminants would pass through the filter and into the detector. 441 The invention was not directed to a new type of aspirator or fan. It was well known before the priority date for smoke detection systems to include fans either to drive or draw air through the system. I accept the evidence that the location of the fan upstream or downstream of the detector was not a matter involving ingenuity. 442 By reason of the units which were marketed and sold before the priority date, including the VESDA E700 range and the Olsen D51B, it was known before the priority date: (1) that there were two ways of transporting air to smoke detectors and they were by the use of air-conditioning ductwork and by the use of a dedicated network of sampling pipes; (2) in a case where air-conditioning ductwork is used only part of the total volume of air from the air-conditioning is taken into the detector; (3) it was common, in order to avoid soiling or contamination of the detector, to fit a filter upstream of the detector; (4) it was common to include the detector and other components, such as a filter and fan, in a housing; (5) tubular detection chambers were naturally suitable for, and commonly used in, smoke detectors using light scattering principles such as the VESDA E700 units; (6) it was necessary for the sample of air to be taken quickly from the area being monitored to the detector, and speed was an important factor in the performance of smoke detection systems; and (7) as it was necessary for the air to be transported from the area being monitored to the detector, it was common to use a fan or a pump. 443 The question is whether it is practically certain or whether I can be clearly satisfied that the bypass arrangement embodied in claims 1, 3, 4 and 6 in the specification would have been obvious to a person skilled in the relevant art in the light of the common general knowledge as it existed before the priority date in Australia. I remind myself of the onus on the respondent. I also remind myself that obvious means very plain, that a scintilla of inventiveness is sufficient and that I must guard against the misuse of hindsight. I have considered the evidence advanced by the applicant and the evidence advanced by the respondent. I have reached the conclusion that the bypass arrangement would have been obvious to a person skilled in the relevant art. 444 I accept the evidence of Messrs Jawerth, Johnson and Piik-Wakeling as to the two broad options in terms of solutions to the filter-clogging problem and I accept their evidence that developing a new filter medium or mechanism would have been time-consuming and costly. A bypass arrangement whereby a sample of air was used was already something that had been developed in the industry with the increasing use of air-conditioning duct sampling units such as the Olsen D51B unit and the VESDA E700 units following the ban on the placement of point-detectors in air-conditioning ducts. 445 I also accept the evidence of Mr Johnson that the skilled worker in the smoke detection industry would start with an existing system rather than commence development of a completely new system. The VESDA E700 units were the most well-known aspirating smoke detection system in Australia and they had been marketed and sold for more than 10 years. The skilled addressee would know that in terms of taking a sample of air an air-conditioning duct and a dedicated sampling pipe performed the same function and operated upon the same principle. 446 It seems to me that it would have been very plain to a skilled worker that the filter-clogging problem could be solved by arranging for a sample of air to be taken from a main flow in a dedicated sampling pipe and passing only that smaller sample of air through a filter and detector. There was no reason to think that that solution could not be implemented and would not work. The design and arrangement of pipework to create a main duct and a secondary duct and to maintain a sufficient rate of airflow was a straightforward matter for designers and installers of smoke detection systems at the priority date. Mr Piik-Wakeling said in one of his affidavits that if the bypass arrangement as a solution to the filter-clogging problem had not been obvious to him by itself before July 1993, "it would certainly have been very obvious to me in view of the Brown article". He was asked about that statement in the course of cross-examination. The effect of his evidence was that one could never be absolutely certain that a system would work until it had been up and operating for a long period of time. I do not think that Mr Piik-Wakeling's reservation amounts to evidence by him that the bypass arrangement or the invention was not very plain because further tests were required. 447 It is not strictly necessary for me to consider the respondent's alternative submission that the bypass arrangement would have been obvious to a person skilled in the relevant art in the light of the common general knowledge as it existed in the patent area before the priority date of the relevant claim together with the Brown, Moores and Birkby article. However, I will do so in case the conclusion I have reached is incorrect.

The Brown, Moores and Birkby article 448 A symposium was held in the Connaught Rooms, London, between 8 and 10 March 1972. The Symposium appears to have been conducted by Joint Fire Research Organisation and others and a number of papers were presented at the Symposium. Those papers were later published. The general description of the proceedings was "Symposium No 6 Automatic Fire Detection" 449 One of the papers presented at the Symposium was the Brown, Moores and Birkby article. I have already set out the title of the article. The article contains an abstract and the following headings: Introduction Description of milling plant Development of the technique Results and discussion Future work Conclusion Acknowledgments 450 There are various figures or drawings in the article and of present importance is Figure 20.2 "Schematic Layout of a Typical Monitoring System". 451 The following features of the article may be noted. The particular subject discussed in the article is fires in coal pulverising mills. The combustion product to be analysed is carbon monoxide. A problem identified is the rapid blockage of the sampling system with fine coal dust. The problem is said to be solved by using a sampling probe which separates the pulverised fuel and air by a stainless steel sinter inside the ducting. 452 After describing types of milling plants the authors of the article describe the reasons fire detectors based on light emission or obscuration and smoke detection cannot be used and the reasons testing of carbon monoxide levels is used: "Both mill designs incorporate regions where coal is in contact with hot air but remote from the moving components, and it is this coal which constitutes the main fire risk. Fire detection is complicated by the high level of vibration produced in both types of mill, by the light obscuring properties of the coal/air mixture and by the erosive nature of the coal itself. Thus fire detectors based on light emission or obscuration and smoke detection cannot be used and the use of thermocouples is limited by the number required to ensure that any fire is detected with reasonable certainty. Consequently, a solution has been sought which involves detection of the gas phase products of incipient combustion by sampling the atmosphere at the mill outlet." 453 The principal suggestion made in the article to address the problem of the rapid blocking of sample lines with moist pulverised coal is that the probe be redesigned so that it incorporated a stainless steel sinter of 20mm pore size in the sampling head within the duct. This was said to achieve the following: "… the pulverised coal and air were effectively separated inside the duct and only an extremely fine dust was carried into the sample lines." 454 Figure 20.2 (proceeding from left to right) shows the following. First, there is a probe in a duct and it is this probe which is to have the stainless steel sinter. The air passes through the probe and along a nylon sample line. It passes through a refrigeration device and then through a pump. The air then continues along the line until it reaches a point at which it can travel in either of two directions. It can travel through a vertical pipe or line which appears to have a valve and the drawing has marked on it in relation to this pipe or line "Excess Sample to Waste". Instead of proceeding in that direction some of the air can proceed along the horizontal pipe or line through a filter and then a flow meter and then a gas analyser. 455 In 2006, Mr Kael Driscoll was a reference librarian employed at the Reid Library at the University of Western Australia. His affidavit establishes that the Symposium papers, including the Brown, Moores and Birkby article, were publicly available for borrowing from the Library at the University of Western Australia some time in late 1975. 456 Ms Julie McInerney was employed by the CSIRO in the Manufacturing and Infrastructure Technology Library (MIT Library) in Highett. The Symposium papers, including the Brown, Moores and Birkby article, were part of the collection of the Experimental Building Station Library in Sydney in and after 1974 and held by the CSIRO Division of Building Research in Highett from 17 June 1978. The Symposium papers would have been available for public inspection at those libraries after the dates on which they were received, provided they were not on loan to members of those libraries. 457 The Brown, Moores and Birkby article is only relevant if it meets the test in s 7(3) of the Act. That test adapted to the circumstances of this case is whether the hypothetical non-inventive skilled worker, in addition to his or her common general knowledge, could, before 30 July 1993, be reasonably expected to have ascertained, understood and regarded as relevant to work in the relevant art in Australia the Brown, Moores and Birkby article. Whether something could be reasonably expected requires a prediction. In Federal Commissioner of Taxation v Peabody (1994) 181 CLR 359 the High Court said (at 386): "A reasonable expectation requires more than a possibility. It involves a prediction as to events which would have taken place if the relevant scheme had not been entered into or carried out and the prediction must be sufficiently reliable for it to be regarded as reasonable."

(Citations omitted.) (See also Futuris Corporation Limited v Commissioner of Taxation [2010] FCA 935.) 458 In the context of s 7(3) of the Act the question is whether, having regard to the evidence, it may be reasonably predicted that the hypothetical non-inventive skilled worker faced with a filter-clogging problem before the priority date would have ascertained, understood and regarded as relevant the Brown, Moores and Birkby article. 459 The dispute between the parties related to the acts of ascertaining and regarding as relevant. There was no dispute that the hypothetical non-inventive skilled worker would have understood the Brown, Moores and Birkby article. I have read the article more than once and I do not think such a worker would have failed to understand it. 460 There is an overlap between the acts of ascertaining and regarding as relevant. It is possible that a person might obtain part of the article such as the abstract, but not obtain the whole article. 461 Some general points should be made at the outset. 462 Evidence that a non-inventive skilled worker who did in fact face the filter-clogging problem before July 1993 did or did not find the Brown, Moores and Birkby article would have some weight in terms of what a hypothetical non-inventive skilled worker might reasonably be expected to have done. 463 Evidence from a non-inventive skilled worker that had he been faced with the filter-clogging problem in July 1993 he would have found the Brown, Moores and Birkby article may be given weight, depending on the reasons advanced in support of the opinion. Considerable weight might be given to a person who has done a search, albeit after the priority date, and is able to explain with some precision how he or she would have found the article. Less weight and perhaps no weight would be given to a person who simply asserts that he would have found the article. 464 I accept the evidence that a non-inventive skilled worker faced with a problem for which the solution was not obvious is likely to carry out searches of scientific and industry journals. That was the evidence of Mr Jawerth, Mr Johnson and Mr Piik-Wakeling. In the case of Wormald (Aust) and Mr Jawerth, there were specialised search services (Wormald (Aust)'s Central Technical Services Department) and in the case of Mr Johnson and Mr Piik-Wakeling there were librarians within the organisations. Certainly from time to time detailed searches were carried out in the fire detection field. 465 A search could start with a search of the titles to articles or of the abstract of articles. According to Mr Jawerth and Mr Johnson the abstract was the more important. Mr Jawerth and Mr Piik-Wakeling said, and I accept, that the search terms would be modified as the matter proceeded. 466 I accept the evidence that the search terms and criteria would have included "fire detection", "sampling", "combustion" and "blockage". 467 I accept that a search using these terms or criteria would have led to the Brown, Moores and Birkby article because the Symposium is called "Automatic fire detection" and the title of the article is "The early detection of fires in coal pulverizing mills by measurement of carbon dioxide". The abstract includes terms and words such as "Fire detection", "a sample", "blockage" and "sampling system". In a general sense, a coal pulverizing mill would be an environment where forms of dust could create filter-clogging problems. 468 Mr Johnson said, and I accept, that a search would not be restricted to literature dealing with smoke particles. A broader search would be carried out. Mr Jawerth and Mr Johnson said, and I accept, that similar problems were faced in both the smoke detection and gas detection and analysis fields, and both use a similar filtering principle. Mr Barrett said he would not restrict himself to smoke particles, but would also consider the detection of gaseous impurities, such impurities being one of the byproducts of fire, and Mr Bray said that he would have looked at other industries where the filtration of airstreams might have led to a problem of filter blocking. As the respondent submitted, this point is reinforced by the fact that each version of the specification prior to the current one makes it clear that the invention is applicable to the detection of a variety of impurities including not only smoke but also gaseous impurities such as methane. 469 I accept Mr Johnson's evidence that the article was not irrelevant because it dealt with gas detection and not smoke detection. The article was about the use of analysers and filters in dirty environments. 470 I reject the suggestion that a search would be limited to literature published after the early 1980s when filters were first introduced in VESDA smoke detection systems. I accept Mr Johnson's evidence that ionization detectors were introduced in the 1940s and that a considerable amount of work on fire detection was done in the 1960s, 1970s and 1980s and that the skilled worker would go back to that period. 471 The evidence of Dr Cole and Mr Barrett makes clear that the VESDA E700 had been used in Australia in a similar environment (that is, a coal mill) to that described in the Brown, Moores and Birkby article. Furthermore, the environment is one in which filter-clogging was likely to be a problem. 472 I also accept the evidence of a number of witnesses that, had they obtained the Brown, Moores and Birkby article for the purpose of addressing a filter-clogging problem, Figure 20.2 would have been of particular interest to them. That evidence was given by Mr Barrett, Mr Jawerth and Dr Cole. 473 There is no reference in the article to the filter before the gas analyser becoming blocked with unwanted contaminants. 474 The library catalogue at Monash University included references to other major libraries including CSIRO libraries. I accept Mr Johnson's evidence that if he had been conducting research, one of the libraries he would have visited was the Department of Building, Construction and Engineering at the CSIRO. 475 Mr Anthony Jennings is a patent searcher with tertiary qualifications in science. From 1991 to 2000 he worked as a patent and trademark searcher. In 2000 he set up his own company. Mr Jennings' work has and does involve not only patent and trademark searches, but also searching for scientific and technical records. 476 In September 2007 Mr Jennings was asked to conduct a search of patents and literature generally, relating to the topic of smoke alarms using only such searching facilities available at 30 July 1993. He was informed of the filter-clogging problem and given the names of companies and inventors who were active in the smoke alarm field prior to July 1993. He was asked to conduct a "state of the art" type search to ascertain what, if anything, had been proposed prior to 30 July 1993 for reducing or overcoming the filter-clogging problem. 477 Mr Jennings outlined the various databases and then set out the steps he would have undertaken in order to ascertain the relevant literature. 478 Mr Jennings first identified the patent literature he would have found. He then turned to the non-patent literature. 479 Mr Jennings said it is common for consideration to be given to obtaining the enhanced title or abstract, then the full database record and then the document itself. 480 Mr Jennings said that in the search he conducted the Brown, Moores and Birkby article was not found. Nor were the Cerberus patent or the Nohmi patent. 481 The significance of Mr Jennings' failure to locate the Brown, Moores and Birkby article must be assessed having regard to the following: 1. He is a patent searcher, not a person skilled in the relevant art or a librarian. 2. He did not have a client to consult during the conduct of his search. Discussion with a client who was skilled in the field may have led him in different directions in terms of his searches. 3. His searches were limited to the electronic data bases available to him. He did not visit libraries or check library catalogues. 4. The electronic databases searched by Mr Jennings did not include fire detection or fire protection as specific subjects and did not index specialist fire industry publications. 5. There was a difference of significance between the results of the patent searches and the results of the scientific searches; by comparison the results of the searches in relation to scientific literature were "a bit low". There is "more commercial results" from the patent databases so they get first priority. 482 There is a good deal of force in the respondent's submission, based on the evidence of Mr Johnson, that the CSIRO library was one of the primary sources of information for fire engineers and that a person skilled in the art and facing of filter-clogging problem would carry out a search of that library or arrange for a librarian to carry out a search on his or her behalf. 483 There is also a good deal of force in the submission that had the person skilled in the art obtained the Brown, Moores and Birkby article a bypass arrangement would have been apparent from Figure 20.2. 484 However, I think the chain of reasoning breaks down at the intermediate stage. I am not satisfied that the person skilled in the art, having obtained the title to the article or the abstract of the article, would as a matter of a reasonably reliable prediction have obtained the complete article including Figure 20.2. There is no evidence as to how many titles or abstracts would have been revealed by the search. It may have been a large number of articles including the title or abstract of the Brown, Moores and Birkby article. The teaching of the abstract of the Brown, Moores and Birkby article is the inserting of a sintered filter in the probe of a sampling line. The abstract does not contain any teaching, at least directly, of a solution to a filter-clogging problem. To my mind, there is no sufficient basis in the evidence to conclude that even if the title or abstract of the article had been obtained, the skilled worker would have ascertained and regarded as relevant the whole article. 485 These conclusions are against the background of Dr Cole not finding the article when he was faced with a filter-clogging problem in 1992. Furthermore, none of the experts who gave evidence for the respondent conducted a search for the purposes of giving evidence and therefore they were not in a position to give evidence of the precise steps whereby they would have obtained the Brown, Moores and Birkby article. 486 I find that the Brown, Moores and Birkby article does not meet the requirements of s 7(3) of the Act.

Claims 2, 5, 7 and 13 in the specification 487 Claims 2, 5, 7 and 13 in the specification contain the additional feature that the whole of the airstream passes through a detection module through which extends said main duct means and which contains said secondary duct means, said filter and said detecting means. The respondent contends that this feature does not involve an inventive step. 488 Mr Jawerth said, and I accept, that in 1993 nearly all the smoke detectors that were available on the market were a collection of parts in a housing or a box and that enclosing the components or parts in a box did not affect the operation of the system unless the box itself operated as a duct. The Olsen D51B unit consisted of a housing which enclosed parts of two probes, a filter and a detector. The VESDA E700 Mk II was designed and supplied as an integrated unit which consisted of a steel box or housing with pipes, a filter, a detector and a fan. The evidence was that the steel box or housing made the VESDA E700 Mk II unit easier to install. Mr Fox believed that the feature involving the detection module had the advantages of convenience of installation, reliability and neatness of appearance after connection. The VESDA E700 Mk III unit was in a plastic enclosure which was about the size of an ordinary briefcase and it contained pipes, a filter, a detector and a fan. 489 Mr Barrett said that there is nothing in the specification that identifies an advantage in putting the main duct means, secondary duct means, filter and detector in a box and that to do so was "quite possibly" within the competence or skill set of an engineer working with an installer. 490 I do not think the additional feature in claims 2, 5, 7 and 13 in the specification involved an inventive step.

Claims 8 and 14 in the specification 491 Claims 8 and 14 in the specification contain the additional feature that an aspirator is located in the main duct means and upstream of the secondary duct means for the purpose of forcing air through the main duct means and secondary duct means. Fans were used in smoke detection systems before the priority date and the evidence establishes that whether the fan was upstream or downstream was simply a matter of design choice depending on the specific installation. 492 I do not think the additional feature in claims 8 and 14 in the specification involved an inventive step.

Claims 9 and 15 in the specification 493 Claims 9 and 15 in the specification contain the additional feature that the said sampling duct means includes a plurality of sampling pipes. As I have said, before the priority date the VESDA E700 units were used in connection with air-conditioning ducts or dedicated sampling pipes. The Olsen D51B unit was used in conjunction with air-conditioning ducts. Mr Fox agreed that if an air-conditioning duct was a main duct means of a sampling duct means of a smoke detection system then the air-conditioning ducts took the form of a plurality of sampling pipes within claims 9 and 15. 494 When the VESDA E700 units were used with a dedicated network of sampling pipes there was a plurality of sampling pipes within claims 9 and 15. 495 I do not think the additional feature in claims 9 and 15 in the specification involved an inventive step.

Claims 10 and 16 in the specification 496 Claims 10 and 16 in the specification contain the additional feature that the detecting means comprises a single detector. 497 Each of the VESDA E700 Mk II and Mk III and the Olsen D51B units were supplied with a single detector and that was common general knowledge at and before the priority date. 498 I do not think that the additional feature in claims 10 and 16 in the specification involved an inventive step.

Claims 11 and 17 in the specification 499 Claims 11 and 17 contain the additional feature that the said detector includes a tubular housing. 500 The VESDA E700 units had tubular detection chambers. That allowed for a more efficient airflow through the detection unit because there was less friction between the air and the detection wall chambers through which the air flowed. In addition, it was easier to provide an airtight seal. 501 The VESDA E700 Mk I comprised a tube containing an optical sensing chamber. A light source flashed across the chamber thereby illuminating any airborne particles which were present and scattering the light into the path of the sensing chamber. A smoke detection unit called the Hartnell smoke detection unit also had a tubular detection chamber. The VESDA E700 Mk II and Mk III had a detection chamber which was in the shape of a long cylinder. 502 I do not think that the additional feature in claims 11 and 17 in the specification involved an inventive step.

Claims 12 and 18 in the specification 503 Claims 12 and 18 in the specification contain the additional feature that the said detecting means comprises a semiconductor optical emitter. 504 A light emitting diode ("LED") light source and a laser light source both fall within the description of a semiconductor optical emitter and at the priority date were the two main types of such emitters. 505 A Xenon flash tube was used in the VESDA E700 units. It was well known that they were unreliable. The VESDA LaserPlus which was designed in 1995 used a laser diode. 506 The Olsen D51B unit used an LED as a light source, as did the Hochiki duct detection unit. By comparison with incandescent light sources, LED had the advantage of reliability and a low power consumption. 507 The use of lasers in aspirating smoke detection systems was well known before the priority date. Lasers had been used by a company called Hartnell Microelectronics (later Kiddi Hartnell) since the 1980s. The laser light source was very reliable. 508 In the late 1980s, Hartnell Microelectronics was based in Cramlington in the United Kingdom. It was a competitor of IEI (Aust) and (UK). Hartnell released a smoke detection unit which used a laser onto the market in the United Kingdom sometime in the late 1980s and this unit was released in Australia in the late 1980s or the very early 1990s by Kiddi-Graviner. Kiddi-Graviner purchased Hartnell prior to 1993 and became known as Kiddi Hartnell. 509 Mr Johnson said, and I accept, that there was a major trend in the industry to replace incandescent light sources with LEDs. At the priority date in Australia a skilled addressee would consider semi-conductor LEDs and lasers as two alternatives to the Xenon flash tube. 510 I do not think that the additional feature in claims 12 and 18 in the specification involved an inventive step.

Introduction 511 At the relevant time, the Act provided that a ground of opposition to the grant of a standard patent was that the nominated person was not entitled to a grant of a patent for the invention (s 59(a)). The subject of entitlement was dealt with in s 15 of the Act and, relevantly, for present purposes, the person entitled to a grant of a patent for an invention was the inventor (s 15(1)(a)). 512 The respondent pleads that the applicant is not entitled, or is not solely entitled, to the grant of a patent for the invention because the applicant does not derive title to the invention from the inventor or any person entitled to have a patent arising from the invention assigned to them and further, or alternatively, the applicant or its predecessors in title obtained all or a part of the invention from the respondent. The respondent's particulars of these grounds are as follows: "(1) the development by Michael Scully of a prototype installation in or around early 1992 (2) the development by Peter Fox of the E7 Az-Pyr detector whilst in the employ of IEI (UK) Limited." 513 In its final submissions, the respondent made it clear that it did not press the second particular, namely, the development by Mr Fox of the E7 AZ PYR detector whilst in the employ of IEI (UK). 514 The respondent submits that if there is an inventive concept in the claims in the specification, it is the use of a simple bypass arrangement to reduce contaminants reaching the filter by causing a large proportion of air sampled from the protected area(s) to bypass the filter and detector assembly, so that only a smaller representative sample of the air passes through the filter and detector assembly. 515 The respondent's case is that Mr Scully, who was an employee of IEI (UK) in 1992, designed and built in that year a smoke detection system which embodied a bypass arrangement and that the idea of that arrangement was communicated to Mr Fox and Mr Girling during their employment by IEI (UK). 516 The Patent application identifies the inventors as Mr Fox, Mr Girling and a Mr Mark Symonds. The applicant's evidence is that it was Mr Fox who conceived the idea of a bypass arrangement. I refer to the discussion set out in [41]-[44] and [380] above. 517 The applicant's case is that nothing Mr Scully did anticipated the inventive concept or idea embodied in the Patent application or, if his work did involve the inventive concept or idea it was not communicated to either Mr Fox or Mr Girling.

Relevant principles 518 The respondent carries the onus of proof on the entitlement issue: Stamp v W J Powell Proprietary Ltd (1918) 24 CLR 339; Montecatini Edison SpA v Eastman Kodak Co (1971) 45 ALJR 593, [1972] RPC 639. 519 A passage in the 8th edition of Terrell on Patents (published in 1934) at pp 18-20 contains the relevant principles for the purposes of this case: "It must be remembered that the question "Is the patentee true and first inventor?" is entirely separate and distinct from the question "Is the invention itself new?" In the former case we are dealing with the history of an idea in the mind of a particular man; in the latter with the history of a manufacture.

The difference was pointed out by Tindal CJ in Gibson and Campbell v Brand (1 WPC 627 at 628): 'The defendant next says that these letters patent have not been granted to the true and first inventors, which you are aware is a condition required by the statute. Now a man may publish to the world that which is perfectly new in all its use, and has not before been enjoyed, and yet he may not be the first and true inventor; he may have borrowed it from some other person, he may have taken it from a book, he may have learnt it from a specification; and then the legislature never intended that a person who had taken all his knowledge from the act of another, from the labours and assiduity or ingenuity of another, should be the man who was to receive the benefit of another's skill.'

In Tennant's case (1 WPC 125 n) a material part of the invention claimed was found to have been suggested to the patentee by a chemist at Glasgow. Lord Ellenborough held that the patent was invalid, inter alia, because the grantee was not the inventor. It will be observed in this case, that although it is possible that the patentee was the first person to use the particular method for making bleaching liquor, nevertheless he was held not to be the inventor, because the particular method of producing this bleaching liquor was thought out by someone else and communicated to him.

In Cornish v Keene (1 WPC 501 at 507), Tindal CJ said: 'Sometimes it is a material question to determine whether the party who got the patent was the real and original inventor or not; because these patents are granted as a reward, not only for the benefit conferred upon the public by the discovery, but also to the ingenuity of the first inventor; and although it is proved that it is a new discovery, so far as the world is concerned, yet if anybody is able to show that although that (ie the publication to the world) was new, that the party who got the patent was not the man whose ingenuity first discovered it, that he borrowed it from A or B, or had taken it from a book that was printed in England, and which was open to all the world - then, although the public had the benefit of it, it would be an important question whether he was the first and original inventor of it.' There is no doubt that, in the circumstances stated by the Chief Justice, the person obtaining the patent would not be the true and first inventor.

The principle laid down in the cases cited above has invariably been followed.

A may have invented something; he made have made a few experiments with the invention, and then abandoned it (without publication). B may subsequently have invented the same thing, altogether independently of A. If B applies for letters patent he is at law the first inventor; but if it is shown that the process of invention was not carried on in B's mind at all, but that A communicated his ideas to B, although with the full intention of abandoning them, B will not be the first inventor.

In Lewis v Marling (1 WPC 490 at 496) Bayley J, said: 'If I discover a thing for myself, it is no objection to my claim to a patent that another also has made the discovery, provided I first introduce it into public use.' (ie communicate the invention to the public in a specification.)

The suggestion in that case was that the patentee had acquired his invention by seeing a model of a similar machine which had been brought from America. It was disproved that he had seen the model, and consequently he was held to be the first and true inventor. (And see Permutit Co v Borrowman (1926) 43 RPC 356 (PC) at 359)." This passage was cited with approval by the Full Court of this Court in Stack v Davies Shephard Pty Ltd (2001) 108 FCR 422 at 431-432 [19]; (2001) 51 IPR 513 at 520-521. I refer also to JMVB Enterprises Pty Ltd v Camoflag Pty Ltd (2005) 67 IPR 68 at 93-94 [130]-[133]. 520 In a case such as this where it is said that the applicant is not entitled to the patent because the invention was made by another and communicated to the applicant, there is a three-stage inquiry. First, it is necessary to identify the inventive concept in the patent or patent application. Secondly, it is necessary to identify the inventive concept in the ideas of the person alleged to be the true inventor. Finally, assuming a match in response to the first two questions, it is necessary to determine whether the inventive concept was communicated to the applicant by the person alleged to be the true inventor. 521 The Full Court of this Court considered the issue of how a court first determines the inventive concept of a patent or patent application in Polwood Pty Ltd v Foxworth Pty Ltd (2008) 165 FCR 527. The Full Court (Finn, Bennett and Greenwood JJ) said at 543 [60]: "The invention or inventive concept of a patent or patent application should be discerned from the specification, the whole of the specification including the claims. The body of the specification describes the invention and should explain the inventive concepts involved. While the claims may claim less than the whole of the invention, they represent the patentee's description of the invention sought to be protected and for which the monopoly is claimed. The claims assist in understanding the invention and the inventive concept or concepts that gave rise to it. There may be only one invention but it may be the subject of more than one inventive concept or inventive contribution. The invention may consist of a combination of elements. It may be that different persons contributed to that combination." 522 I turn now to address facts which are not in dispute.

The facts 523 I can start with facts which were not in dispute. 524 In the early 1990s, Glaxo, a large pharmaceutical company, was planning to build a installation at Stevenage in the United Kingdom and the buildings which were to comprise the installation needed to have fire or smoke detection systems. The project was a very large one and there was evidence before me that from IEI (UK)'s point of view it was the biggest single-site project opportunity after the Channel Tunnel project. 525 Glaxo engaged Ove Arrup and Partners to prepare engineering drawings and specifications for the project. Wormald Britannia were Glaxo's preferred installer as far as the fire or smoke detection systems were concerned. 526 At some stage, IEI (UK) was approached to tender for the supply of smoke detection systems for the project. As I understood the evidence, IEI (UK)'s usual products were not suitable for the project because they were too expensive for what was required. A smoke detection system with a lower sensitivity than normal would be adequate for the project. It was considered that a particular product would have to be developed for the project. 527 In 1992, there were a number of meetings between representatives of IEI (UK) and Wormald Brittania. The representatives of IEI (UK) from time to time were Mr Fox, Mr Scully and Mr Frank Trubshaw and the representatives of Wormald Brittania were (principally) Mr Raymond Walsh and Mr Michael North. 528 Mr Fox was very keen for a product he or Mr Girling had developed called the E7 AZ PYR to be offered to Wormald Brittania for use in the project. That product was really a composite of parts of other products that were then on the market. It included a detector chamber from Autronica A5 of Norway, being the same device which was used in the AutroSense BW 50 detector, and a control panel taken from the VESDA model E700D. 529 Dr Cole did not support the idea of the E7 AZ PYR being offered to Wormald Brittania for use in the Glaxo project. The product to be offered to Wormald Brittania became a matter of serious dispute between Mr Fox and Dr Cole and correspondence in October and November 1992 recording that dispute was tendered in evidence. 530 In October 1992, Dr Cole travelled from Australia to the United Kingdom and on 30 October 1992 he summarily dismissed Mr Fox from his employment by IEI (UK). On Saturday 1 November 1992, there was a meeting at the premises of IEI (UK) at Stevenage ("the Stevenage premises") which was attended by Mr Fox, Dr Cole and others. The purpose of the meeting was to enable Mr Fox to put his case for reinstatement. 531 Some time later, IEI (UK) secured a contract to supply smoke detection systems for the Glaxo project and the product supplied under the contract was called a VESDA Scanner. 532 Mr Scully was employed by IEI (UK) from July 1989 to the end of 1996. For the last four years of his employment he was general manager of the company. In 1992 he was employed as the company's technical manager. 533 I turn now to address those areas where there was a dispute between the parties. 534 Mr Scully said that with a view to developing a product which might be used in the Glaxo project he carried out modifications to an existing product called a Locator and that those modifications embodied a bypass arrangement. Mr Scully prepared a memorandum dealing with his modified Locator and he had others within the company prepare drawings of his design including a drawing marked "C". He constructed a prototype of the modified Locator and placed it on the back wall of the Stevenage premises. That was all done, according to Mr Scully, in 1992 and before Mr Fox left his employment by IEI (UK). The respondent asks me to conclude that Mr Fox or Mr Girling saw the drawings or prototype or both and that that was the origin or source of Mr Fox's idea of a bypass arrangement. 535 Mr Scully was able to produce a copy of the memorandum from the outset, but in December 1999 he was unable to produce the drawings he had had prepared. For the purposes of the opposition before the Commissioner, Mr Scully drew what he believed was shown on the drawing marked "C" and attached to his memorandum. I will refer to the original drawing as "C" and to Mr Scully's recreation of the drawing as the 1999 drawing. 536 Mr Scully made a second statutory declaration for the purpose of the opposition proceedings before the Commissioner on 20 February 2001. A second recreation of the drawing marked "C" was prepared by the respondent. Mr Scully said that it showed the design of his modified Locator. I will refer to this drawing as the 2001 drawing. The 2001 drawing is similar to the 1999 drawing. It identifies the enclosure as a cabinet but, unlike the 2001 drawing, it shows an exhaust pipe out of the cabinet. 537 Mr Scully said that his records showed that his memorandum was saved on 27 April 1992. He said that he believed that he gave the memorandum to Mr Trubshaw on or about that date. He believed that, in accordance with usual company practice, Mr Trubshaw would have shown the memorandum and sketches to Mr Fox and to representatives of Wormald Brittania. 538 To test his modified Locator, Mr Scully constructed a prototype using the pipework system and VESDA detector at the Stevenage premises. His model was placed on the back wall of the premises and it was there for between a few days and about a week. It was, according to Mr Scully, visible to people working in the Stevenage premises and to visitors. 539 Mr Scully said that, in what he called "its final implementation", the filter before the aspirator would be removed because there would be no need for such a filter. 540 It seems that some time in late 2002 or very early 2003, Mr Scully was provided with a copy of his original memorandum and the attached drawings, including the drawing that was marked "C". There are differences between the drawing "C" on the one hand, and the 1999 drawing and the 2001 drawing on the other. The configuration of the pipework within the housing is different and, in particular, the drawing "C" shows air being piped out of the housing into an exhaust pipe rather than into the housing. 541 Mr Scully wrote to a Mr David Estrela by facsimile transmission on 26 February 1993. He set out a drawing of a unit he had thought of for a special application IEI (UK) had. The drawing shows air being sucked through a pipe by a fan and then some of it being exhausted into the atmosphere and some of it going through what is called a locator pipe. No filter is shown. In the course of his message, Mr Scully said: "We did a mock-up here and it worked OK?" 542 Mr Scully said that the mock-up was the prototype he put on the back wall of the Stevenage premises. 543 In cross-examination Mr Scully said the prototype he constructed was on the bench near the back wall. "It would be for a few days … I would have said a week or two weeks at the most." 544 Mr Scully also said that the exhaust shown on the 2001 drawing should not be shown as there would be no use for it. 545 Mr Scully was an honest witness. However, I have reservations about his reliability. First, he did not seem to have a strong independent recollection of events at the time he gave evidence. That was understandable having regard to the time which had elapsed since the relevant events. Secondly, there were differences between the various drawings to which I have already referred. Thirdly, it is difficult on Mr Scully's evidence to form a precise picture of the prototype on the rear wall of the Stevenage premises and I am uncertain as to how it would have appeared. Finally, it is unclear from Mr Scully's evidence how long the prototype was on the rear wall of the Stevenage premises. 546 Mr Frank Trubshaw gave evidence by video link from Great Britain. He was an honest witness. In 1991 and 1992, Mr Trubshaw was employed by IEI (UK) in a sales capacity. He learnt of the Glaxo project in 1991. He saw the memorandum and sketches prepared by Mr Scully in April 1992. He showed them to Mr Walsh and Mr North in April or May 1992. He was aware of Mr Scully's prototype which was in place in about April 1992 for about a week or two. He said the IEI (UK) premises were protected by an IEI-developed detection system and he said it was not uncommon for the fire detection system to be used "to test various configurations and to demonstrate those configurations to actual or potential clients". The prototype was examined by the two representatives of Wormald Brittania. Mr Trubshaw does not give any direct evidence of Mr Fox or Mr Girling receiving the memorandum and drawings or seeing Mr Scully's prototype. Importantly, Mr Trubshaw said the prototype accorded with the device shown in the first recreated sketch. 547 In cross-examination, Mr Trubshaw agreed that IEI (UK) was offering the Locator product after Mr Fox had left the employment of IEI (UK). 548 Mr Raymond Walsh gave evidence by videolink from Great Britain. He was an honest witness. Between 1991 and 1997 he was employed by Wormald Brittania as a fire systems engineer. Wormald Brittania was appointed as Glaxo's fire protection installer in 1992. Mr Walsh and Mr North were appointed to the project and they spoke to IEI (UK) (Mr Trubshaw) and Cerberus. In May 1992, Mr Trubshaw raised with them the use of a product called a Locator. They saw a model of a modified Locator on the rear wall of IEI (UK) at the Stevenage premises. They had discussions with Mr Scully. He and Mr North also had discussions with Mr Fox about a product called the E7 AZ PYR. The product which was ultimately used in the project was called a Scanner. 549 In cross-examination, Mr Walsh said that Wormald Brittania was appointed the fire protection installer for the Glaxo project in October 1992. He said that his discussions about the Locator occurred before he and Mr Fox agreed on a price for the E7 AZ PYR. 550 Mr Walsh was adamant that his discussions about the Locator product took place in May 1992 and that after the E7 AZ PYR was withdrawn the negotiations turned to the VESDA E700 D Single Unit or Scanner. I make the point at this stage that the correspondence, particularly the IEI (UK) letter to Wormald Brittania dated 3 November 1992 and Wormald Brittania's letter to IEI (UK) dated 26 November 1992, strongly suggests that the E7 AZ PYR was withdrawn at about the time Mr Fox was dismissed and that thereafter the parties focused on the VESDA E700D or the Scanner. For example, by 3 November 1992, IEI (UK) was writing to Wormald Brittania saying: "4. Our primary objective is to supply the IEI VESDA Scanner system." 551 Mr Christopher Girling was employed by IEI (UK) from 1988 to 1993. He was employed as an engineer. Mr Girling resigned from his employment with IEI (UK) in February 1993. 552 As I have said, Mr Girling died in 2002 and he was not cross-examined on his affidavits. 553 Mr Girling developed the E7 AZ PYR. He had partially developed it at the time he was asked by Mr Fox to develop a cheaper product which would meet the specifications for the Glaxo project. He completed work on it, but was then told it would not go any further because Dr Cole had told Mr Fox that the E7 AZ PYR was not to be used in the Glaxo project. 554 Mr Girling said that during his employment with IEI (UK) the Stevenage premises was protected by a VESDA smoke detection system attached to the rear wall of the ground floor of the premises. The system was never used to test new ideas or new products. Mr Girling said that the making of prototypes was his responsibility within the company and he never saw a model or test installation on the rear wall of the premises. He could not recall Mr Scully suggesting a solution for the Glaxo project which involved the Locator product. Furthermore, he never saw Mr Scully's memorandum and sketches. Mr Girling stated that Mr Trubshaw's recollection about the number of people who were employed by IEI (UK) in 1992 was wrong. Mr Girling said that Mr Scully's modified Locator as shown in the 1999 drawing and in the 2001 drawing was impractical because it had a filter in a place where one was not necessary and yet no filter - other than what he called sintered bronze silencers - where one was necessary. 555 Mr Fox agreed with Mr Girling. He said that he would not have allowed the smoke detection system in the Stevenage premises to be used for testing purposes. Mr Fox never saw a prototype or model on the rear wall of the Stevenage premises. He was never presented with any proposal which would involve the use of a modified Locator for the Glaxo project. He would have vetoed any such proposal because he had concerns about the pump used in the Locator. Mr Fox said that the item called "filter" in each small-bore tube in the Locator product was a bronze, sintered, pneumatic silencer supplied by Norgren Martonair Ltd. Mr Fox had a diary entry showing a meeting with representatives of Wormald Brittania on 13 July 1992. He said that the first formal meeting anyone from IEI (UK) had with representatives of Wormald Brittania in relation to the Glaxo project was a meeting he attended on 13 July 1992. 556 There were meetings thereafter and, according to Mr Fox, Wormald Brittania, and Ove Arrup and Partners, accepted the E7 AZ PYR for the project. He made the point that there was a working VESDA smoke detection system at the premises. Mr Fox produced some pages of the specifications for the Glaxo project which are dated April 1992. Mr Fox said the Glaxo project was not finished until 1995. 557 I have already referred to Mr Mitchell who was employed by IEI (UK) between 1989 and 1994 as a commissioning engineer. His job was to set up and test a smoke detection system once it was installed. He also returned to sites in the event of some fault arising. There was a VESDA smoke detection system installed at IEI (UK) premises and he never saw it adapted to be part of a testing system. He never saw a prototype on the rear wall of the premises and he agreed that, if there had been one, anyone working in the premises would have seen it.

The issues 558 I refer to the three issues identified in [520] above. 559 In terms of the first issue, I have set out the respondent's explanation of the inventive concept. I will proceed on the basis that that is an adequate description. 560 The second issue is whether Mr Scully's memorandum and drawings and his prototype embodied the inventive concept embodied in the Patent application. As I understand it, it is not necessary for me to be satisfied that Mr Scully came up with his idea of the modified Locator because he considered a bypass arrangement would protect the filter. Nevertheless, I do not think that drawing "C" or the prototype embodies the inventive concept. I do not think it would occur to anyone that there was a bypass arrangement so that air bypassed the filter. Of the two possible "filters" shown on drawing "C" the most obvious one is the filter before the aspirator; there is clearly no bypass arrangement in relation to that filter. There is also a strong argument that the sintered filter is not disposed in a secondary duct means. 561 I turn to consider the third issue in case I am wrong in relation to the second issue. 562 The parties made very detailed written submissions about the evidence and the findings the Court should make. It is fair to say that there is conflicting evidence on almost every factual issue. The relevant events happened many years ago. 563 I have found it helpful to examine whether there is an event which is clearly established on the evidence and, if so, to examine the other issues based on the timing of that event. 564 The correspondence shows that in October 1992 and shortly prior to Mr Fox's dismissal, Mr Fox was promoting the E7 AZ PYR for the Glaxo project. Dr Cole was opposed to this course and he wished to promote the VESDA scanner. The offer to supply the E7 AZ PYR was withdrawn and this caused a good deal of friction between IEI (UK) and Wormald Brittania. There is a letter from IEI (UK) to Wormald Brittania dated 3 November 1992 and a response from Wormald Brittania to IEI (UK) dated 26 November 1992. That correspondence shows that at that point Wormald Brittania was looking for IEI (UK) to supply the VESDA E700D single unit with an option to supply the scanner or AZ PYR for the Glaxo project, and IEI (UK) was looking to supply the IEI VESDA Scanner system for the Glaxo project. 565 IEI (UK) eventually secured the contract and the Scanner was the product which was supplied. 566 It seems to me that in those circumstances, it is most unlikely that Mr Scully would have been carrying out tests or experiments on a different product at that point in time. I find on the balance of probabilities that if Mr Scully carried out tests and experiments on a Locator product he did so before Mr Fox was dismissed from his employment by IEI (UK). 567 I find on the balance of probabilities that Mr Scully did carry out tests and experiments on a Locator product. The memorandum and sketches, his evidence and the evidence of Mr Trubshaw and Mr Walsh establishes that fact. 568 I am not entirely confident that that was done in April or May 1992 rather than a little later but for present purposes it does not matter. 569 I am not prepared to find on the balance of probabilities that Mr Fox or Mr Girling saw or were given a copy of Mr Scully's memorandum and sketches. I accept that it is an available inference that Mr Fox did; after all this was a very large project and Mr Fox was the managing director of IEI (UK). One would have expected him to have seen it or to have received it. However, he said that he did not and there was no direct evidence that he did. I listened to Mr Fox's cross-examination on this issue very carefully and I formed the view that I could accept his evidence on this issue. 570 I find on the balance of probabilities that Mr Scully prepared a prototype of his modified Locator and that he showed it to Mr Walsh and Mr North. I find that the prototype was at the rear of the workshop, but I am unable to make a finding as to precisely how it was configured in terms of the rear wall and a bench near the rear wall. I accept the evidence that it was unlikely to have been connected to the existing fire or smoke alarm system. 571 I am not able to make a finding as to what a person looking at the prototype would conclude in terms of the alleged bypass arrangement. 572 I find that the prototype was at the rear of the workshop, possibly on display, only for a short period of time being a week or less. It is not possible on the evidence to be more precise than that. 573 I find that none of Mr Fox, Mr Girling or Mr Mitchell saw the prototype. I accept there is an available inference to the contrary particularly having regard to the layout of the Stevenage premises and Mr Fox's evidence. However, I listened carefully to the evidence and cross-examination of Mr Fox and Mr Mitchell and I am not satisfied that they were telling other than the truth when they said that they did not see a prototype at the Stevenage premises. 574 I should add that in reaching my conclusions about Mr Fox's evidence on this topic, I have taken into account his evidence about discussing the Locator with Mr Walsh. It is by no means clear that he is referring to the modified Locator as distinct from the Locator which was one of the standard products offered by IEI (UK). 575 In my opinion, the respondent's opposition based on a lack of entitlement must fail.

Conclusions 576 A summary of my principal conclusions is as follows: 1. The priority date of the claims in the specification is 30 July 1993. 2. The expression in the claims "main duct means in the form of sampling duct means of a smoke detection system" includes an air-conditioning duct. 3. The bypass arrangement was anticipated by the following: (1) The published material identified earlier in these reasons in relation to the VESDA E700 units and the use of those units in association with air-conditioning ducts. (2) The published material identified earlier in these reasons in relation to the Olsen D51B units and the use of those units in association with air-conditioning ducts. (3) The photographs and explanations by Dr Cole in Australia of the smoke detection system at CERN. (4) The Cerberus patent. 4. I am not satisfied that the bypass arrangement was anticipated by the following: (1) The smoke detection systems at Billy Guyatts Moonee Ponds, Billy Guyatts Blackburn and Radio Australia, respectively. (2) The Nohmi patent. 5. None of claims 1-18 inclusive in the specification involved an inventive step. 6. The respondent has not made out its case of a lack of entitlement. 577 I will give each party leave to make submissions as to the final orders to be made having regard to these reasons. I certify that the preceding five hundred and seventy-seven (577) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Besanko.