Expo-Net Danmark A/S v Buono-Net Australia Pty Ltd

REASONS FOR JUDGMENT 1 The applicant (Expo-Net) is the patentee of Australian Patent No 2006226731 (the Standard Patent) and Australian Innovation Patent No 20070100339 (together, the Patents). The Patents have a common specification, although the claims are different. The Patents relate to a method of producing structural elements of a contact filter block and an apparatus for producing structural elements of a contact filter block. Expo-Net claims that the respondents (together, Buono-Net) have infringed the Patents by way of a Buono-Net product identified by the mark "Bio-Tube". Buono-Net has cross-claimed for revocation of the Patents on a number of grounds. 2 By its amended notice of motion, Buono-Net seeks: an order under s 31A(1) of the Federal Court of Australia Act 1976 (Cth) (the FC Act) giving summary judgment for Buono-Net on its cross-claim revoking the whole of the Patents; and an order under s 31A(2) of the FC Act summarily dismissing Expo-Net's application. 3 The basis of Buono-Net's summary dismissal application is that the specification common to the Patents does not 'describe the invention fully, including the best method known to the applicant of performing the invention' as required by s 40(2)(a) of the Patents Act 1990 (Cth) (the Act). Pursuant to s 138(3)(f) of the Act, the Court may revoke a patent on the ground that its specification fails to comply with s 40(2). Buono-Net relies on what it calls the "second limb" of s 40(2)(a), the requirement that the specification describe the best method known to Expo-Net of performing the invention at the time of filing the patent application. 4 In support of its application, Buono-Net relies on the affidavit evidence of John Klinkby, the inventor of the method and the apparatus of the Patents.

LEGISLATION 5 Section 31A(1) of the FC Act relevantly provides: The Court may give judgment for one party against another in relation to the whole or any part of a proceeding if: … (b) the Court is satisfied that the other party has no reasonable prospect of successfully defending the proceeding or that part of the proceeding. 6 Section 31A(2) of the FC Act relevantly provides: The Court may give judgment for one party against another in relation to the whole or any part of a proceeding if: … (b) the Court is satisfied that the other party has no reasonable prospect of successfully prosecuting the proceeding or that part of the proceeding. 7 Section 31A(3) of the FC Act states that for the purposes of s 31A, a defence or a proceeding or part of a proceeding need not be "hopeless" or "bound to fail" for it to have no reasonable prospect of success. 8 The application of the test in s 31A was recently considered by the High Court in Spencer v Commonwealth of Australia (2010) 241 CLR 118 and by the Full Court in Kowalski v MMAL Staff Superannuation Fund Pty Ltd (2009) 178 FCR 401. Relevantly, the following emerges from Spencer (discussed in Apotex Pty Ltd v Les Laboratoires Servier (No 4) (2010) 89 IPR 274) and Kowalski: The phrase 'no reasonable prospect' should be interpreted by giving full weight to the section as a whole. Section 31A applies if and only if the Court is satisfied that there is 'no reasonable prospect' of success. The effect of s 31A was to soften the test for successful application of summary judgment as stated by the High Court in Dey v Victorian Railways Commissioners (1949) 78 CLR 62, General Steel Industries Inc v Commissioner for Railways (NSW) (1964) 112 CLR 125 and Theseus Exploration NL v Foyster (1972) 126 CLR 507. There is a discretion reposed in the judge hearing an application to grant summary judgment. The exercise of the power under s 31A should be attended with caution and involve a high degree of certainty about the ultimate outcome of the matter if the matter were to go to trial. More complex cases are unlikely to be capable of being resolved by summary judgment without discovery and oral evidence. Where an application requires consideration of apparently complex questions of fact, the questions are unlikely to be capable of being resolved without conducting a mini trial on the documents without discovery and without oral evidence. Section 31A does not entail inquiry directed to whether a certain and concluded determination can be made that the proceedings would necessarily fail. The section will apply in a case in which there is unanswerable or unanswered evidence of a fact fatal to the pleaded case and any case which might be propounded by permissible amendment. Section 31A(2) requires that practical judgment be made. Where there are factual issues capable of being disputed and in dispute, summary dismissal should not be awarded simply because the Court has formed a view that an applicant is unlikely to succeed on the factual issue. Where there is a real issue of fact to be decided it is generally appropriate that the matter goes to trial. Section 31A is designed to deal with cases that are not fit for trial (per Lord Hope in Three Rivers District Council v Bank of England (No 3) [2003] 2 AC 1 at 94-95, cited with approval by French CJ and Gummow J in Spencer at [26]; however note the distinction drawn by Hayne, Brennan, Kiefel and Bell JJ at [51] between the reference in the English Civil Procedure Rules 1998 to 'no real prospects' and s 31A's criterion of 'no reasonable prospect'). The inquiry is whether there is a reasonable prospect of prosecuting the proceeding, not as to whether a certain and concluded determination could be made that the proceedings would necessarily fail, in contrast to the test in Dey and General Steel. The question for determination is, as the section requires, whether there is no reasonable prospect of success. Some examples could be a finding involving words such as "clearly", "manifestly", "obviously", "frivolous", "untenable", "groundless" or "faulty" but these expressions do not substitute for the statutory test.

Issue for Determination 9 For the purposes of this application, it is necessary to examine the allegation of a failure by Expo-Net to describe the best method known to it of preparing the claimed invention as required by s 40(2)(a) of the Act. 10 If Expo-Net has no reasonable prospect of defending the allegation, Buono-Net is entitled to an order revoking the Patents.

THE BEST METHOD OF PERFORMING THE INVENTION 11 Before turning to a discussion of the Patents and the evidence relied upon by Buono-Net, it is relevant to note five matters. 12 First, questions of patentability bases are complex and the different grounds of alleged invalidity may interrelate in evidence and submission. 13 Second, the allegation of failure to disclose the best method is but one ground of alleged invalidity of the Patents. Evidence has been filed in support of other alleged grounds, such as lack of inventive step. 14 Third, the requirement to describe the invention fully must take into account the fact that that description is directed to the person of ordinary skill in the art. That is, by using the word "describe", s 40(2)(a) does not import a requirement to describe details which would be well-known and understood by the skilled addressee. For example, there is no requirement to include in the specification details of well-known analytical agents, commonly used methods, well-known terms of art, or a description of machinery in standard use. Otherwise, a patent would not only of necessity run to substantial length but it would also make it difficult to wade through the morass of unnecessary detail in order to ascertain the invention. 15 Fourth, as a factual matter, it must be established that there was a better method known to the applicant as at the date of filing of the patent than the one described in the specification. This is clearly a subjective question. 16 Fifth, the issue for determination involves the method of performing the invention. To that end it is necessary first to understand what the invention is. Indeed, this is perhaps the first question that needs to be answered. In Enka BV v E I Dupont De Nemours & Co (1987) BP 13 (TPD), a decision of the Supreme Court of South Africa Transvaal Provincial Division, Harms J (with whom Ackerman and Van Zyl JJ agreed) discussed s 23(1)(h) of the South African Patents Act 1952 which provided that the complete specification must 'disclose the best method of performing invention known to the applicant at the time when the specification was lodged at the Patent Office'. I see no distinction for present purposes between the word "disclose" and the requirement in s 40(2)(a) that the best method be "described". Justice Harms said that an applicant for revocation must show that: (a) the method which the patentee failed to disclose is a method of performing the invention; (b) the method is in fact a better method of performing the invention than the method disclosed in the specification; (c) the method was known to the patentee at the time when the application for the patent was lodged at the Patent Office; (d) the method is not disclosed in the specification; and (e) the patentee knew that the method was better than the method(s) described in the specification. That analysis is, with respect, useful. 17 In order to ascertain the best method of performing an invention, the cases illustrate that it is necessary first to understand what the invention is and to consider the method described in the Patents of performing that invention. The two may need to be considered concurrently. In Colgate Palmolive Co v Cussons Pty Ltd (1993) 26 IPR 311 at 354, Sheppard J distinguished a method claim from a method of manufacture involved in the invention where the claims were claims limited by result. There was, as his Honour pointed out, nothing new involved in the method of manufacture. Justice Sheppard noted (at 355) that a required level of flowability was an essential feature or element of the invention. The specification purported to describe a method of testing relative flowability, but failed to describe the best method of conducting the test known to the applicant, in that it failed to mention the need for an essential element of the test. His Honour concluded that, as the invention would not have been performed unless the resulting embodiment had the required flowability, a failure to describe the best method of testing flowability known to the applicant was a failure to describe an essential part of the best method of performing the invention (at 355). 18 In Firebelt Pty Ltd v Brambles Australia Ltd (2000) 51 IPR 531, the inventor had asserted that the claimed device, which opened a lid at any time, would be ineffective. The primary judge had concluded that the failure to describe in the specification a factor critical to the claimed invention, that is the timing of a lid opening device, meant that the best method of performing the invention had not been disclosed. The Full Court emphasised (at [48]) that a patentee acting uberima fide must give the best information in his or her power on how best to carry out the invention and noted that the inventor is not limited to claiming only the best way of carrying out the invention. The Full Court reiterated that it is part of the consideration for the grant of a statutory monopoly that the inventor give to the public sufficient instruction to work the invention without the need for any new inventions or inventive additions, which of itself obliges the inventor to disclose the best method of performing that invention of which he or she knows. This last requirement has been noted over time (see e.g. Blanco White in Patents for Inventions, 4th ed, Stevens, 1974 at para 4-502). As French and Lindgren JJ (with whom Crennan J agreed) observed in Pfizer Overseas Pharmaceuticals & Ors v Eli Lilly & Co (2005) 225 ALR 416 at [374], the requirement that an applicant disclose the best method known to him or her of performing the invention safeguards against an applicant's holding back with a view to getting the benefit of a patent monopoly without conferring on the public the full consideration for the grant of that monopoly. 19 The Full Court held in Firebelt that as the claimed invention was not of a particular lid opening device operating at any particular time, there was no statutory obligation to describe the preferred timing (at [52]). This is because, as the Full Court said at [53], 'the patentee is required to give the best information in his power as to how to carry out the invention' (emphasis added), that is the invention as claimed. As the Full Court said, if a particular lid opening device operating at a particular time had been claimed, a failure to include those matters in the specification might be such a failure. It was not. 20 In each of these cases, the Court examined the claimed invention and then determined whether the best method of performing the invention had been described. It is necessary to follow this approach here.

The Invention of the PatentS 21 The Patents are entitled "A contact filter block, a method of producing structural elements of a contact filter block and an apparatus for producing structural elements of a contact filter block". Claim 1, the relevant claim for this application, is to: A method of producing structural elements of a contact filter block using an apparatus including: a reservoir for storing granulate material having a first melting point, said reservoir having a first inlet and a first outlet, said granulate material including a foaming additive having a second melting point, a heating and pressurising unit including a chamber having a second inlet and a second outlet, said second inlet in communication with said first outlet, a path of travel defined from said second inlet to said second outlet, said heating unit including heating and pressurising elements distributed along said path of travel, an extruder unit mounted downstream relative to said heating and pressurising unit at said second outlet, said extruder unit further including an extruder heating unit and two oppositely rotating extruder heads or two parallel moving extruder heads defining an extruder outlet, said extruder unit generating a mesh-type tubular structure, a cooling unit mounted at said extruder unit for rapidly cooling said granulate material, and a measuring and cutting device for measuring and cutting elements having a predetermined length within a specific interval. the method including the steps of: supplying said granulate material to said heating and pressurising unit from said reservoir via said second inlet, conveying said granulate material along said path of travel, heating said granulate material to an elevated temperature and pressurising said granulate material to an elevated pressure while conveying said granulate material along said path in said heating and pressurising unit, said heating and pressurising performed according to a specific heating and pressurising profile, transferring said heated and pressurised granulate material to said extruder unit, heating said granulate material within said extruder heating unit to a temperature above said first melting point and/or at or above said second melting point, extruding said mesh-type tubular structure from said granulate material, said heating of said granulate material causing an expansion of said foaming additive causing said mesh-type tubular structure to obtain a porous structure, cooling said extruded mesh-type tubular structure by said cooling unit according to a specific cooling profile thereby stopping or halting expansion of said granulate material and/or said foaming additive and locking or fixating said porous structure of said mesh-type tubular structure, and cutting said mesh-type tubular structure using said measuring and cutting unit. [emphasis added] 22 The specification common to the Patents states that the invention relates, relevantly, to a method of producing structural elements of a contact filter block, a contact filter block obtained by the method and an apparatus for producing structural elements of a contact filter block using the method. It can be seen that the elements utilised to produce the contact filter block include: a reservoir; granulate material; foaming additive that forms part of the granulate material; a heating pressurising unit; an extruder unit; a cooling unit; and a measuring and cutting device. 23 The method includes the steps of: supplying granulate material to the heating and pressurising unit from the reservoir; conveying the granulate material; heating the granulate material and transferring it to the extruder unit; heating the granulate material within the extruder unit; extruding a mesh-type tubular structure; heating the granulate material causing expansion of the foaming additive causing the mesh-type tubular structure to obtain a porous structure; and cooling the unit which stops or halts the expansion cutting the tubular structure. 24 As stated in the specification, the basic idea of the invention is to provide improvements to the structural elements of the contact filter blocks for improving the properties of those blocks. 25 Buono-Net's revocation claim for failure to comply with s 40(2)(a) concerns the foaming additive. The specification says that the term 'a foaming additive' is: to be construed as a generic term including any material present in solid, liquid or gaseous phase which allows the granulate material to be expanded for providing the porous structure of the mesh-type tubular structure produced in accordance with the method according to the first aspect of the present invention. 26 'Granulate material' includes any material conventionally used in the polymer or plastic industry in the extrusion technical field. 27 The method is primarily directed towards the advantageous properties of the structural elements produced according to the invention, namely the enlarged surface originating from the release of the foaming additive. The larger surface area so produced provides space for columns of bacteria usable in the decomposition of waste or biological material in water. As described in the specification, the foaming additive, on heating, reaches a foaming space and causes an expansion or creation of bubbles in the material, thereby creating a porous structure in it. This may be done in the extruder heating unit or in the heating and pressurising unit. The expansion is stopped by means of a cooling unit. 28 A preferred granulate material is specified amongst different granulate materials described. No particular foaming agent is specified although a range of percentages and a preferable weight of the foaming agent as a percentage of the weight of the granulate material is stated. The specification also states that the granulate material comprises a foaming additive that, when heated above a certain (unspecified) temperature expands and thereby creates bubbles in the melted or soft granulate material. The specification further states that as the 'material includes a foaming additive that is released above a certain temperature, the foaming material will enter a gaseous state thereby creating a porous structure in the material'. 29 In summary, the foaming additive is used in the production of the structural elements of the contact filter block which, upon heating, expands and provides a porous structure of the elements which increases their surface area to enable the block formed of those structural elements to be of greater use in the growth of bacterial colonies for waste management. A class of granulate material is described, including the preferred granulate material. No foaming additive is specified. Rather, it is described by its properties and function. 30 There is no dispute that the foaming additive is an essential integer of the claims. The claims do not specify any particular foaming additive. The only further claimed characterisations within the claimed method are in claim 2 of the Patents, that the weight of the foaming additive constitutes 3 to 10 per cent of the weight of granulate material, and in claim 5 of the Patents (the apparatus claim), in which the foaming additive has a melting point apparently different to that of the granulate material.

Buono-Net 31 Buono-Net relies on evidence filed by Expo-Net in an affidavit of the inventor, Mr Klinkby. Mr Klinkby describes the steps taken in the development of the "BIO-BLOK", apparently the contact filter block of the invention, produced by the claimed method. The first date of filing of the Patents was 23 March 2006. Mr Klinkby's affidavit describes a period, relevantly, from 2000 to 2001. 32 Mr Klinkby states that when experimenting with a particular granulate of material he incorporated: …some foaming agent into the formulation to foam the product creating a fluffier product with 'give' so it would absorb some force. At that time I was aware that foaming agent could be used to make a product fluffier and bigger, giving it better insulating properties and reducing the amount of raw material needed to manufacture the product (thus also making it cheaper to manufacture). 33 Mr Klinkby says that he thought that he might be able to incorporate foaming agent into the BIO-BLOK in order to roughen the surface. This was in the context of looking for a cheaper product. He explains that he was not sure if that foaming agent would work and that he had certain concerns about it but thought that it might be possible to use foaming agent to achieve the roughness and reduction in the raw materials he needed. 34 Mr Klinkby then decided to test whether he could use foaming agent and still achieve a viable product, by testing a number of different foaming agents using a specific granulate of material, "virgin HDPE". This was in order to remove variables introduced into the extrusion process. He obtained a number of foaming agents that were compatible with HDPE - approximately six over a period of six months. He tested each foaming agent in increasing percentages, keeping all other parameters the same. By the end of the tests (in about 2001) he found, as stated in his affidavit, that: a. One or two of the foaming agents I tried did not create a rough surface at all. b. One or two of the foaming agents did produce a somewhat rough surface. c. At least two of the foaming agents caused the products to foam too much which made the extrusion impossible to control, and no useable product resulted. 35 Mr Klinkby says that at the end of the series of experiments, he discounted the foaming agents that did not work and picked the one foaming agent that provided the best result. He says: I was very surprised by the amount of roughness I could achieve with this foaming agent, without the foaming becoming uncontrollable and thus the product unuseable. However I was still concerned that even with this foaming agent the resulting product would not be viable. 36 In about 2003, Mr Klinkby then carried out other experiments. He conducted further tests on the same virgin HDPE and a foaming agent but changed other parameters such as temperature, using the temperature and pressure of the foaming agent as a starting point for the parameters. The temperature and pressures to foam were not relevant to the production of the rough surface and Mr Klinkby did not consider them relevant to his testing. Mr Klinkby says that as there were a large number of variables to test and a large number of combinations of those variables, the experiments took two to three years, between approximately 2001 and 2003. He says 'eventually I discovered a combination of parameters that produced a product using foaming agent that still had the other required characteristics'. He says that he tried to use the minimum foaming agent required to produce a rough surface and to foam as little as possible, thereby minimising or preventing disadvantages. 37 One of the integers of the claimed method, and one of the variables, is the extrusion line used. One of the variables in the method is the extruded speed. Mr Klinkby says that the accuracy of the manufacturing equipment is important because of the small amounts of foaming agents used. In November 2004, Expo-Net purchased a further extrusion line, which enabled the measurement of small quantities of foaming agent. In February 2005, Expo-Net first manufactured BIO-BLOK using foaming agent on that extrusion line. 38 As a further aspect of his experimentation, in the early 1990's Mr Klinkby had developed a process using "regrind". This produced a contact filter block with a rough texture. A customer of Expo-Net told Mr Klinkby that he or she had observed that the rough tube worked better than the smooth tubes. Mr Klinkby says that this was the first time that he realised that rough textured tubes could be advantageous in wastewater treatment. An attempt to use both a foaming agent and a regrind was unsuccessful. The claimed contact filter block does not include regrind. 39 Buono-Net seeks to draw from Mr Klinkby's evidence the conclusion that the inventor tried five or six foaming action agents of which only two produced useful, "surprising" results. The remaining foaming agents either did not produce a rough surface, resulted in the product blowing out or produced a somewhat rough surface. It is to be recalled that the claim is to a foaming agent without distinction. 40 Buono-Net accepts Expo-Net's characterisation of the invention as the idea that a beneficial rough (porous) surface and a contact filter can be achieved by using foaming agent as a part of an extrusion process whereby granular material and foaming additives are used in the one operation as defined in the claim. Accepting that the claim is not limited to the best method of carrying out the invention, Buono-Net emphasises that there is a good faith requirement to give the best information as to how to carry out the invention. Buono-Net submits that the failure on the part of the inventor to disclose that the use of some foaming agents did not achieve the claimed invention and the failure to disclose those negative foaming agents each represented a failure on the part of Expo-Net to describe the best method in accordance with s 40(2)(a) of the Act. 41 There is no suggestion by Buono-Net that any other aspect of the claim and the particular arrangement of equipment and process steps described in the specification is not the best method known to the inventor. In its written submissions, Buono-Net asserted that there was also an insufficiency of description, in that there was insufficient information to enable a person with ordinary skill to work the claimed invention, but Buono-Net did not press this ground of invalidity at the hearing of its s 31A FC Act application.

Expo-Net 42 Expo-Net submits that the "best" method of the invention is not a particular foaming agent formulation but a description of a process. Expo-Net points to evidence that the use of foaming agents was part of the common general knowledge of those engaged in the extrusion of plastics generally and that the means by which foaming agents could be added to granulate material to achieve a porous structure was within the routine skill of the calling. Expo-Net's submissions are to the effect that there was no need to disclose those matters to the reader skilled in the art. 43 For example, Mr Benetti, an Expo-Net witness, said in his affidavit that getting the right balance in the use of foaming agents is a matter of trial and error and that not all foaming agents produce a rough surface. Mr Benetti said that 'once a decision is made to use foaming agent to make a rough surface, it is a matter of juggling the parameters to deliver that end'. Other expert witnesses referred to the adjustment of parameters in the course of making extruded pipe. There was also evidence in particular as to the variability of the characteristics of different foaming agents in that they foam at different rates and temperatures. It is to be recalled that in Mr Klinkby's experiments, which are the subject of the evidence relied upon by Buono-Net, all of the variables were maintained as a constant save for the different foaming agents. 44 Mr Benetti also said that 'knowing the information regarding the method and apparatus disclosed in the Standard Patent, in particular as shown in the figures, it would be a routine matter for me to choose a suitable foaming agent and set up an extrusion line to manufacture contact filter blocks which fell within the surface area and… values given'. 45 Mr Newstead, a Buono-Net witness, confirmed that foaming agents may be of different strengths or may have slightly different constituents, which makes exchanging brands difficult in some cases. He also said that the temperature and pressure profile is important to the efficacy and stability of the foaming agent. According to Mr Newstead, different machines have different machine processing characteristics so that processing parameters are "tweaked" to suit each target machine setup. In particular, Mr Newstead's evidence is that with, at most, a small amount of trial and error he could, prior to the priority date, have been able to reproduce the claimed product and that, providing the correct dye and equipment was sourced, "fine-tuning" of the product could be completed within two weeks of production. 46 Expo-Net points out that Buono-Net's expert witnesses note that there are no data in the Patents as to which type of foaming agent is to be used or a preferred type, yet it is part of Buono-Net's case on invalidity that the claimed invention was obvious in the light of common general knowledge as at the priority date. 47 Expo-Net characterises the claimed invention as a method of achieving a resulting product. Expo-Net submits that the invention as disclosed and as described in the specification teaches those skilled in the art how they might achieve an advantageous form of contact filter block. Expo-Net submits that the process includes within it the concept of the use of a foaming agent and that any foaming agent may be used in combination with the other parts of the process as identified to achieve the results of surface porosity. The surface porosity is achieved and described by result, which recognises that there are a number of process variables that must be manipulated by the person of skill. Expo-Net submits that the process is one by which a foaming agent (any foaming agent) of choice may be used in combination with other process elements to achieve a result. 48 Expo-Net points to the evidence of expert witnesses adduced by both parties to the effect that the choice of a suitable foaming agent and its use to achieve the desired result is a matter of routine and within common general knowledge. Expo-Net contends that it is no more a requirement that particular information about one foaming agent used by the inventor be supplied than it would be to require identification of a particular brand or model of equipment used as the extruder or cooling unit. 49 Expo-Net also submits that a proper reading of Mr Klinkby's affidavit makes it apparent that the evidence relied upon by Buono-Net of the foaming agents which did not work or worked poorly related to an experimental stage leading up to the invention, where Mr Klinkby deliberately and artificially fixed all other variables and was using a particular extruder that has since been replaced. Expo-Net emphasises that the invention is not the choice of particular foaming agents but a process using foaming agents together with other machine parts and materials to achieve a result. 50 Further, Expo-Net submits, Buono-Net has not established that the confined and restricted processes the subject of those experimental results were the best method known to Mr Klinkby as at the priority date.

Consideration 51 The claimed invention is to a process utilising a number of parameters, being ingredients and machinery, to achieve a desired result. While some of the dependent claims give more specificity, generally speaking there is no claimed limitation on the different integers of the combination. That includes the foaming agent. There is evidence that the foaming agent is susceptible to temperature and that different foaming agents will melt, which they must do for the process, at different temperatures. This may depend in turn on the other integers of the combination. 52 The Patents define foaming agent by reference to the desired result to be achieved. 53 Where a claimed invention is described without limitation or further specificity with regard to the individual integers, an argument that the description in the specification is insufficient may be available. However, this would normally be within what has been described as the first limb of s 40(2)(a), that is that there is insufficient instruction to enable the person of ordinary skill to work the invention without inventive step or undue experimentation. However, that is not the basis for this application. Buono-Net says that there was a best method of performing the invention known to the inventor and not disclosed. 54 In my view, Expo-Net has a reasonable prospect of defending Buono-Net's cross claim for revocation for failure to comply with s 40(2)(a) of the Act on two bases: There is evidence in the proceedings that the skilled reader of the specification, whose common general knowledge is relevant in an assessment of necessary disclosure of the method of performing the invention, finds the invention obvious and says that it is a matter of routine to achieve the result claimed. Mr Klinkby's evidence relates to an early period in the experimentation leading to the invention. Importantly, the claimed invention involves an interaction of integers and routine adjustment of variables to obtain a workable result from the use of foaming agent. Mr Klinkby's evidence was of experiments in which all of those variables, other than the use of foaming agent, were fixed. This may or may not affect the working of the foaming agent in a practical performance of the invention. 55 The High Court pointed out in Spencer that care must be taken in making an order under s 31A of the FC Act, in particular in cases involving complex facts. It is a complex question to determine the need for a description or disclosure of details of the choice of foaming agent to the skilled reader where there is expert evidence that such matters were part of the common general knowledge of the person of ordinary skill in the art and were matters of routine experimentation. The determination of the need for the description of particular foaming agents, or the consequences of the fact that some foaming agents did not work in the experimental process, is not one that lends itself to this application. Not only is there conflicting evidence on the subject, there is also the question of the relevance of those experimental results. For example and by analogy, evidence would need to be led to establish whether there was a requirement to disclose a failed in vitro test of a compound in artificial conditions when the claimed use of the compound was in vivo under different conditions. It may be that there is such an obligation and that the early experimental results are relevant to the later developed claimed process, but that is not established on the evidence presently relied on. It is not accepted by Expo-Net and Expo-Net's position is, at least, reasonably arguable. 56 It follows that Expo-Net has established that it has reasonable prospects of successfully defending the claim that the inventor failed to disclose the best method known to him. It is reasonably arguable that there was no failure to describe the details of the choice of foaming agent, or the exclusion of certain classes of foaming agent, to persons of skill in the art, any more than it was necessary to describe the kind of machine components in the apparatus of the claim. 57 It follows that Buono-Net's application for judgment under s 31A of the FC Act, on the grounds that there is no reasonable defence to the ground of invalidity based upon a failure to describe the best method known to the inventor of performing the invention as required by s 40(2)(a) of the Act, must fail. This does not predetermine the outcome of this ground of revocation at the substantive hearing of these proceedings. 58 The application should be dismissed. Expo-Net has asked that I reserve the question of costs. I certify that the preceding fifty-eight (58) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Bennett.