E. I. Du Pont De Nemours and Company v Imperial Chemical Industries PLC

3. A working fluid composition as claimed in claim 1 wherein the heat transfer fluid (A) comprises a mixture of:

4. A working fluid composition as claimed in any one of claims 1 to 3 wherein the linear and branched hydrocarbyl groups specified for R¹ are unsubstituted and the carboxylic acid or carboxylic acid ester containing hydrocarbyl group specified for R¹ contains no other substituents.

16. A working fluid composition as claimed in claim 1 substantially as hereinbefore described with reference to any one of the examples.' 7 Example 5 in the specification was as follows: 'In this Example a series of working fluid compositions were prepared comprising varying proportions of a lubricant comprising an ester of pentaerythritol and n-hexanoic acid and a heat transfer fluid comprising 50% by weight of R-134a, 30% by weight of R-32 and 20% by weight of R-125. The lubricant is at least partially soluble in each of the components of the heat transfer fluid and also in the fluid itself. The lower miscibility temperature of each composition was again determined. The compositions were prepared and the lower miscibility temperatures determined using the procedure described in Example 1.

The results are shown in Table 5. In Table 5 it will be noticed that the lower miscibility temperature of some of the compositions is quoted as being less than -50°C. This means that at -50°C phase separation was not observed. TABLE 5 Working fluid composition

% by weight of lubricant % by weight of heat transfer fluid Lower miscibility temperature (°C) 10.2 89.8 <-50 22.0 78.0 -48 29.7 70.3 <-50 41.6 58.4 <-50 48.6 51.4 <-50 60.7 39.3 <-50

It will be appreciated that the binary mixtures of R-134a and R-32 and the ternary mixtures of R-134a, R-32 and R-125 which form the subject of the above Examples can also be used in combination with other neopentyl polyol ester type lubricants to yield viable working fluid compositions. Moreover, binary mixtures of R-134a and R-32 and ternary mixtures of R-134a, R-32 and R-125 comprising different proportions of the constituent hydrofluoroalkanes to the mixtures exemplified above can also be used in combination with neopentyl polyol ester type lubricants to yield viable working fluid compositions.' 8 It should be noted that refrigerants are classified according to a numbering system. It is sufficient for present purposes to know that difluoromethane is known as R-32, 1,1,1,2-tetrafluoroethane is known as R-134(a) and pentafluoroethane is known as R-125. 9 Patent 54480/90, known as 'the Lubrizol Patent', was relied upon by Du Pont before the delegate as anticipating the patent under consideration. Branson J adopted a summary of the specification of that Patent from the judgment of Emmett J in ICI Chemicals v Lubrizol Corporation (1999) 45 IPR 577, at [35]-[45] as follows: 'The specification states that the alleged invention relates to liquid compositions comprising a major amount of at least one fluorine containing hydrocarbon and a minor amount of at least one lubricant. After describing the background of the alleged invention, referring to the ODP of CFCs, the patent states that HCFC-22 and HFC-134a are generally recommended as being alternatives to CFCs in refrigerant applications and that HFC-134a is particularly attractive because its ODP has been reported as being zero. The specification refers to the need for any proposed replacement refrigerant to be compatible with the lubricant in the compressor and the fact that the proposed new alternative refrigerants have solubility characteristics different from the refrigerants presently in use. The specification stated that the problem was particularly evident in automotive air conditioning since the compressors are not separately lubricated but a mixture of refrigerant and lubricant circulates throughout the entire system.

The specification also states that, in order to perform as a satisfactory refrigeration liquid, the mixture of refrigerant and lubricant must be compatible and stable over a wide temperature range. It states that it is desirable for the lubricant to be soluble in the refrigerant at concentrations of about 5 to 15% over a temperature range from minus 40ºC to 80ºC. The specification also states that the refrigeration liquid must have acceptable viscosity characteristics, even at high temperatures, and should not have a detrimental effect on materials used as seals in compressors.

All of the claims made in the specification refer to a "liquid composition". The liquid composition is said to comprise two elements, being a refrigerant and a lubricant. Various alternatives of each, and combinations of those alternatives, are set out in the 26 claims. In each of the claims, more than 50% of the "composition" must be refrigerant and less than 50% must be lubricant. In some of the claims a more specific proportion is specified.

The claims can be divided into three groups. Claim 1 is for:

(A) a major amount of at least one fluorine-containing hydrocarbon containing 1 or 2 carbon atoms; and

(B) a minor amount of at least one soluble organic lubricant comprising at least one carboxylic ester of a polyhydroxy compound containing at least 2 hydroxy groups and characterized by the general formula

Claims 4 to 9 inclusive are generally dependent on claim 1. Claim 1 and claims 4 to 9 all concern HCFCs and involve variations only in the lubricant. Lubrizol concedes that it cannot maintain those claims.

Claims 2 and 3 are dependent on claim 1. However, the variation is in relation to the refrigerant rather than the lubricant. Claim 2 varies claim 1 by providing that fluorine is the only halogen in the fluorine-containing hydrocarbon (A). That is to say, the refrigerant must be an HFC. Claim 3 varies claim 1 by providing that the refrigerant must be R-134a. Lubrizol wishes to maintain claims 2 and 3 but accepts that it will be necessary for an amendment to be made to those claims if claim 1 is deleted.

(A) from 70 to 99% by weight of at least one fluorine-containing hydrocarbon containing 1 or 2 carbon atoms and wherein fluorine is the only halogen present; and

(B) from 1 to 30% by weight of at least one soluble organic lubricant comprising at least one carboxylic ester of a polyhydroxy compound containing at least 2 hydroxy groups and characterized by the general formula

Claims 11 to 17 are dependent on claim 10 and comprise narrowing variations of claim 10. Claim 11 involves variation of the refrigerant disclosed in claim 10 and requires that the refrigerant must be R-134a. Claims 12 to 17 inclusive involve variation of the lubricant disclosed in claim 10.

(A) from 70 to 99% by weight of 1,1,1,2-tetrafluoroethane; and

(B) from 1 to 30% by weight of at least one soluble organic lubricant comprising at least one carboxylic ester of a polyhydroxy compound containing from 3 to 10 hydroxyl groups and characterized by the general formula

Thus, in claim 18 the refrigerant would be R-134a. Claims 19 to 26 are all narrowing variations of claim 18 in which the variation relates to the lubricant.

Each of claims 1, 10 and 18 contains a series of definitions for 'R', 'R1' and 'n', the variables in the formula which appears in each of the claims. The variations of the lubricant in the claims involve changes in the definitions of those variables. The lubricants which are the subject of the patent are synthetic esters. Synthetic esters are the product of the reaction of acids with alcohols. The reaction produces esters and water. The process is referred to as esterification. The claims identify the classes of acids and alcohols which are capable of producing satisfactory esters.

No claim is made for any of the compounds described in the specification. The essence of the alleged invention is the identification of a soluble organic lubricant which is suitable for use in refrigeration systems with HFCs generally and R-134a in particular. Putting it another way, the alleged invention is the identification of a lubricant having the properties described above in relation to HFCs generally and R-134a in particular.' 10 The delegate said in the reasons for decision that it was conceded that the lubricants of component (B) in Lubrizol are the same as the lubricants in Application 658005 and thus the question was whether the anticipation discloses a refrigerant component (A) that is the same as that claimed in Application 658005. The delegate went on to say: 'The expression "at least one fluorine containing hydrocarbon containing one or two carbon atoms" is a shorthand way of specifying a huge range of refrigerant compositions. It is clear that as a purely intellectual exercise, this includes the mixtures of HFC's that are claimed as component (A) of claim 1 of the present application. Thus the intellectual component of the Lubrizol patent encompasses the present claims. But this is not sufficient to establish lack of novelty. In order to determine where the Lubrizol patent has planted its flag, it is necessary to ask what refrigerant compositions would the Lubrizol patent make public to the instructed reader. For this purpose it is necessary to look to the body of the description. … The anticipation explicitly refers to single HFC's, and especially to R-134a. Mixtures of HFC's are mentioned towards the end of the above quote. The intellectual content of the disclosure includes mixtures of HFC's, thus including compositions of the present application.

The critical question is which mixtures are clearly disclosed, or form part of the technical information that the citation makes public. I do not believe that mixtures of any fluorocarbons should be regarded as clearly disclosed. I consider it is reasonable to regard the citation as clearly disclosing mixtures of those fluorocarbons that are themselves specifically disclosed, either as individual components or components of mixtures. [In the present case, that is those that are identified by their code number, e.g. R-22, R-23, etc.] R-32 and R-125 are not specifically referred to in the description. Consequently, it is unlikely that a reader would consider that they had been taught mixtures of HFC's including R-32 or R-125. On this basis I consider that the Lubrizol patent does not disclose a mixture including either R-32 or R-125.

Conclusion on novelty Since component A must have at least one of R-32 or R-125, the Lubrizol patent does not disclose any compositions that would infringe the present application. The Lubrizol patent does not anticipate the present application. It was conceded that other documents would have anticipated the present application if the priority date were deferred. As this is not the case, the other documents are not relevant to this opposition.' 11 The notice of appeal to the Court included the following ground: '4. Novelty The invention, so far as claimed in each and all of the claims of the patent application, was published before the priority date of each of such claim or is otherwise not novel in light of the following acts of publication or use:

(a) Australian Patent No. 54480/90 which was open for public inspection at the Australian Industrial Property Office on 16 November 1990; …' 12 The conclusions of Branson J concerning that ground were as follows (at [68]-[71]): 'I conclude on the basis of my own reading of the Lubrizol patent and with the benefit of the evidence of Professor Ball, and to a lesser extent Mr Symons, that the delegate was clearly wrong in concluding that "it is unlikely that a reader would consider that they [sic] had been taught mixtures of HFCs including R-32 or R‑125" by the Lubrizol patent. I observe that in ICI Chemicals v Lubrizol Corporation [1999] FCA 345, 45 IPR 577 Emmett J concluded, apparently on the basis of a concession, that if the Lubrizol patent was valid it had been infringed when certain air conditioning and refrigeration systems were retrofitted using a refrigerant that was a ternary mixture of R-32, R‑125 and R‑134a and a lubricant that was a synthetic ester.

It was argued by the respondent that the single example of a blend of 2 HFCs referred to in the Lubrizol patent under the heading "Description of the Preferred Embodiments" does not teach the mixture of the patent application. The patent application requires at least 2 HFCs out of R-32, R‑134a and R‑125 and there is no mention of R‑32 or R‑125 in the Lubrizol patent. The answer to this argument in my view is that integer (A) of the invention of the Lubrizol patent is "a major amount of at least one fluorine containing hydrocarbon containing 1 or 2 carbon atoms" and the specification refers to mixtures of fluorine‑containing hydrocarbons including binary and ternary mixtures. HFCs are fluorine‑containing hydrocarbons. Even without the assistance of Professor Ball's evidence, I would have been inclined to conclude that integer (A) is to be understood as encompassing any mixtures of HFC containing one or two carbon atoms. Read as a whole, it seems to me, that the Lubrizol patent discloses an invention principally concerned with lubricants, albeit lubricants useful within refrigerant compositions. I understand the Lubrizol patent, as it seems to me that Emmett J did also, as disclosing in integer (A) of the invention a broad class of potential refrigerants, extending beyond those identified specifically in the preferred embodiments, with which the lubricant of integer (B) might be used. With the benefit of Professor Ball's evidence I am satisfied that a person skilled in the art to which the patent application relates would have so read it.

The fact that, as the respondent submitted, at the date of the publication of the Lubrizol patent, R‑22 was perceived as part of the solution to the problem of finding a suitable replacement refrigerant, seems to me to be of little significance. The Lubrizol patent expressly refers to a fluorohydrocarbon mixture which does not include R‑22. It cannot be understood as disclosing only mixtures which include R‑22, an HCFC.

I conclude that the Lubrizol patent does deprive the patent application of novelty.'

13 Branson J went on to give consideration to the other grounds of opposition relied upon by the applicant. In considering an argument that s 40 had not been complied with, her Honour said (at [119]): 'I conclude that the complete specification does not describe the invention fully as the disclosure, by reason of the incomprehensibility of a crucial passage and the uncertainty of meaning of the expression "partially soluble", would not allow an addressee of the specification to produce something within each claim without new inventions or additions or, prolonged study of matters presenting initial difficulty. In view of my earlier conclusions, it is unnecessary for me to give consideration to the issue of whether the Court may, in an appeal of this kind, allow an amendment to be made.' It is clear enough that the reference to amendment is to a possible amendment to avoid breach of s 40 by virtue of the uncertainty of disclosure that had been found.

Proceeding N1249 of 1999 - Patent Application 654176 14 As Branson J noted (at [121]), the only independent claims in Application 654176 were as follows: '1. A refrigerant composition comprising:

(I) a refrigerant comprising a ternary or higher mixture of:

(b) difluoroemethane and/or 1,1,1-trifluoroethane; and optionally

(II) a lubricant comprising a polyalkylene glycol and/or an ester.

(II) a lubricant comprising a polyalkylene glycol and/or an ester.' 15 It will be observed that claim 10 is indistinguishable from claim 4 in Application 658005 so far as the refrigerant is concerned. The lubricant would be within claim 1 of Application 658005. 16 Branson J decided that the priority date was earlier than that claimed by the applicant. It was conceded that if that were the case, then the application was invalid. Amongst other things, it would plainly have been anticipated by Application 658005. However, Branson J went on to give consideration to the other grounds of opposition. Again, it was alleged that the Lubrizol patent anticipated the claims in question. Branson J concluded as follows in relation to that ground (at [143]-[144]): 'In giving consideration to the Lubrizol Application the delegate, in the decision from which this appeal is brought, drew the same distinction between its "intellectual content" and what it would make public to the instructed reader as he drew in his decision from which the appeal in matter N1248 of 1999 was brought. He concluded, as he had in that decision that while the intellectual content of the disclosure includes mixtures of HFCs, thus including compositions of the present application, it did not in fact disclose a mixture including R‑32, R‑125 or R‑227ea. For the reasons given in [68] above, I conclude that the delegate erred in reaching the above conclusion and that the Lubrizol Application does disclose ternary and higher mixtures of HFCs.

The above conclusion does not, however, lead inevitably to the conclusion that the Lubrizol Application contains "clear and unmistakable directions to do what the patentee claims to have invented" (see General Tire & Rubber Co v Firestone Tyre & Rubber Co Ltd [1972] RPC 457 per Sachs LJ at 486). Having regard to the highly particularised blends of refrigerants claims by the patent application, I conclude that it is not clearly established that the Lubrizol Application deprives the claims of novelty.' 17 The conclusion of the judgment was as follows (at [153]): 'For the reasons set out above, in each of the matters N1248 of 1999 and N1249 of 1999, the decision of the delegate will be reversed and the opposition to the grant of the standard patent upheld. The parties will have an opportunity to agree minutes of the orders to be made, including the order to be made as to costs.'

Orders and Full Court application 18 On 5 April 2002 orders were made in proceeding N1248 of 1999 upholding the appeal, setting aside the decision of the delegate and refusing Australian Patent Application No 658005. ICI sought leave to appeal pursuant to s 158(2) of the Patents Act. One of the grounds of the draft notice of appeal was: 'Her Honour erred in failing to hold that claim 4 of the [Parent Application] was not disclosed by the Lubrizol patent, because the Lubrizol patent did not disclose ternary refrigerant blends within claim 4 of the [Parent Application].' 19 That leave was refused by the Full Court on 23 August 2002 (Imperial Chemical Industries PLC v EI Dupont De Nemours & Co (2002) AIPC 91-818; [2002] FCAFC 264). In the course of the judgment, the Full Court said (at [17]-[20]): 'The primary judge found that integer (A) of Claim 1 of the Lubrizol Patent anticipated integer (A) of PA658005. Integer (A) of the Lubrizol Patent requires that the liquid composition must comprise (in addition to a minor amount of a lubricant) a major amount of at least one hydrocarbon that contains both fluorine and one or two carbon atoms. Integer A of PA 658005 requires that the composition will comprise (in addition to a lubricant) a mixture of at least two hydrofluoroalkanes selected from: · difluoromethane, · 1,1,1,2-tetrafluoroethane · pentafluoroethane

An alkane is a fully saturated carbon or hydrocarbon chain. That is to say, there are as many hydrogen atoms attached to the carbon atoms as possible and only single bonds exist between the carbon atoms. Thus, the specification states that each of the above three compounds is a fully saturated hydrocarbon chain. Each of them contains fluorine and each contains one or two carbon atoms. Thus, difluoromethane contains two fluorine atoms and one carbon atom. Tetrofluoroethane contains four fluorine atoms and two carbon atoms. Pentofluoroethane contains five fluorine atoms and two carbon atoms. Clearly, each of those compounds is encompassed by the description "fluorine-containing hydrocarbon containing one or two carbon atoms". Thus, the use of a liquid composition described in Claim 1 of PA658005 is clearly disclosed by the Lubrizol Patent.

There is no suggestion in the complete specification of PA658005 that a liquid composition comprising a refrigerant that satisfies the description in integer (A) and a lubricant that satisfies integer (B) would be any more effective than, or perform a function different from, a composition comprising a major amount of at least one fluorine containing hydrocarbon containing one or two carbon atoms and the lubricant described in integer (B) of Claim 1 of the Lubrizol Patent. That is to say, PA658005 is not an instance of the selection of something disclosed by the Lubrizol Patent by way of a further inventive step. It is no more than a particular example of the invention disclosed by the Lubrizol Patent.

It is, therefore, crystal clear that a patent granted pursuant to PA 658005 would be revocable. The correctness of that conclusion by the primary judge is attended with no doubt. Accordingly, there would be no utility in granting leave to appeal from her Honour's orders in relation to PA658005. In the circumstances, it is not necessary to consider the other ground upon which her Honour concluded that the opposition to PA 658005 should succeed.'

Divisional Application 20 In the meantime, on 28 March 2002, ICI filed a Divisional Application of Application 658005 under No 29314/02. Divisional Applications are provided for by s 79B of the Patents Act. At that stage it was in identical form to the parent application. No notice of intention to file that Divisional Application was given to either Du Pont or the Court. The proceeding had been stood over by Branson J on 12 March 2002 to 5 April 2002 for submission of draft orders. 21 On 19 December 2002 an examination report issued on the Divisional Application raising the following objection: '1. The invention defined by the claims lacks novelty in the light of:-

This citation was ruled in the Federal Court judgment as rendering the parent of the current application not novel. It is noted that the specification of the current application is identical to the parent document.

See E I DuPont de Nemours & Co v Imperial Chemical Industries PLC [2002] FCA 230 in particular paragraphs 38 to 71.

Note: In the light of the above the Commissioner is considering refusing this application under s. 49(2). You will be contacted early in the new year to arrange a date for a hearing into the matter.' 22 On 2 April 2003 ICI proposed amendments to the specification which had the effect that claim 1 of the Divisional Application would be as follows: '1. A working fluid composition comprising:

(A) a heat transfer fluid comprising a mixture of difluoromethane, 1,1,1,2-tetrafluoroethane and pentafluoroethane; and

(B) a lubricant which is at least partially soluble in each component of the heat transfer fluid said lubricant comprising one or more compounds of general formula: [formula follows]' That claim is similar in scope (although not in form) to claim 4 of the Parent Application and is similar to claim 10 of Application 654176. A delegate of the Commissioner refused the Divisional Application on the basis it lacked novelty and refused an opportunity to propose further amendments. One ground of that decision was that there was an issue estoppel created by the judgment of Branson J but for the fact that the parties were not the same. (Re Application by Imperial Chemical Industries PLC (2003) 60 IPR 610). 23 On 24 October 2003 ICI appealed against that decision to the Court and the matter came on before Crennan J. Du Pont sought leave to appear before Crennan J as amicus curiae and submitted that it was an abuse of process for ICI to reargue before Crennan J a matter decided by Branson J. Leave was refused (Imperial Chemical Industries Pty Ltd v Commissioner of Patents (2004) 213 ALR 399;(2004) 63 IPR 476; (2004) AIPC 92-055 at [36]). The matter proceeded in the absence of Du Pont. 24 In the course of rejecting Du Pont's application for joinder, Crennan J said (at [45]): 'It is relevant to note that it was sufficient for her Honour's [Branson J's] disposal of the proceeding before her to find that Claim 1 of the parent application lacked novelty over the Lubrizol patent. In making that ultimate finding of fact, it was not necessary for her Honour to deal with Claim 4 of the parent application, that is the claim to the specific ternary mixture of HFCs which the applicant now claims. Furthermore, her Honour's finding that integer (A) of the Lubrizol patent encompassed ternary and higher mixtures of HFCs and her implicit finding that the Lubrizol patent taught mixtures of HFCs is not to be confused with, or taken to be equivalent to, a much narrower finding that integer (A), or the Lubrizol patent as a whole, taught that is, disclosed for novelty purposes) the specific ternary mixture of HFCs which the applicant now claims. Her Honour made no such narrow finding and her judgment (at [144]) suggests to me that this was deliberate rather than constituting some inconsistency in her Honour's reasons. Such a narrow finding was unnecessary because it could not be said that the question of whether or not the Lubrizol patent taught the specific ternary mixture of HFCs now sought to be claimed "was a fact fundamental to the decision arrived at" as that phrase is explained by Dixon J. in Blair v Curran (1939) 62 CLR 464 at 532. For me to now consider that narrow issue, on evidence which was not before her Honour, cannot impugn her Honour's decision in relation to a much wider question of anticipation.' 25 On 16 December 2004 it was ordered that the appeal be allowed, that the decision of the delegate be set aside and that the matter be remitted to the delegate to reconsider the application and amendments proposed by the applicant in accordance with the Court's reasons for judgment (see Imperial Chemicals Industries Pty Ltd v Commissioner of Patents (2004) 213 ALR 319; (2004) 63 IPR 476; (2004) AIPC 92-055 at [87]). 26 Crennan J said (at [64]-[68]): 'Questions of anticipation can be difficult in cases where a broad chemical claim in an alleged anticipatory document, in its terms, encompasses many, even thousands of compounds. Questions can arise as to whether such a broad claim in a patent (or even a divisional thereof) discloses, sub silentio, a particular compound from the broad class, which is the subject matter of a later application.

The world‑wide dispute between Beecham Group Limited and Bristol‑Myers Company over a new penicillin, Amoxycillin, is an example of such difficult questions of anticipation: Beecham Group Ltd's (Amoxycillin) Application [1980] 97 RPC 261 (Beecham); see also Bristol‑Myersat 546; ALR 459-60 and University of Georgia Research Foundation v Biochem Pharma Inc(2000) 51 IPR 222 (University of Georgia). In such cases, in the absence of a skilled addressee understanding or perceiving that the specific compound was part of what was taught by the patent or in the absence of an "enabling disclosure" of the particular compound claimed later, the earlier document does not necessarily disclose the particular compound claimed later, despite the fact that such a compound may be encompassed by a general disclosure. A sound account of the relevant distinctions between a "paper disclosure" and an "enabling disclosure" in the field of chemistry is given by Dr S D Barker in University of Georgia at 233 and 237. … The refusal by the Full Court to grant leave to appeal in a brief decision in ICI v Dupont (especially at [18] and [20]) does not foreclose any question, arising on different evidence, as to whether the Lubrizol patent teaches the specific ternary compound of HFCs, which is the subject matter of this proceeding.

In the field of chemistry fine distinctions are often necessary between a "fleeting" or "paper" disclosure or the "intellectual content" of a disclosure on the one hand, and a "disclosure for novelty purpose" or an "enabling disclosure" on the other. Not every disclosure is a "disclosure for novelty purposes." Beecham's case, to which reference has already been made is apposite to this proceeding and illustrates this difficult point: Buckley LJ refers (at 288) to the fact that the parent patent in that case encompassed"the entire field of α-aminopenicillins . . . and literally thousands of these compounds could be made." Buckley LJ also noted (at 286) that an inclusive claim in a patent of addition for "broad spectrum penicillins" must be treated as specifically claiming amoxycillin. Then (at 290), he found that the prior patent of addition contained "no disclosure or promise" or "teaching" that taught amoxycillin (emphasis added). Accordingly, there was no want of novelty, arising out of a paper disclosure in an inclusive phrase.' Later her Honour said (at [83]-[85]): 'In my judgment it is not correct to say that the Lubrizol patent taught the specific ternary mixture of HFCs, R‑22, R‑125 and R‑134a. Accordingly, I would find the present application, as proposed to be amended before the delegate, novel over the Lubrizol patent.

It can be noted this is consonant with the approach of Branson J. to the "reverse infringement" test at [144] of her Honour's judgment in respect of ternary mixtures, which must have included the subject matter of Claim 10 of 654176.

There is no inconsistency between findings numbered (i)-(v) in [82] above and findings made by Branson J. in the earlier decision. In my view her Honour did not make any express finding on the subject matter of finding numbered (vi) above which I would regard as both careful and deliberate given her Honour's findings at [144] of her judgment. Accordingly, there is no genuine inconsistency between the finding numbered (vi) in [82] above and her Honour's conclusions in respect of the parent application.' 27 On 14 March 2005 the Divisional Application was formally amended. The Application was accepted on 15 March 2005. After advertisement, Du Pont filed the notice of opposition and correspondence followed between the parties in which Du Pont asserted, and ICI denied, that the decisions of Branson J and the Full Court created issue estoppels as to novelty which bound the conduct of the opposition proceedings. That denial led to the present proceeding for a declaration and other relief.

Decision 28 In my respectful opinion, the decision and reasoning of Crennan J were correct. The decision by Branson J as to the lack of novelty of Application 658005 was entirely based upon consideration of claim 1 in the light of the Lubrizol patent and the Full Court, on the leave application, approached the matter in the same way. Branson J noted that claim 1 was the only independent claim and dealt with it. It followed that all dependent claims, including claim 4, fell with the invalid principal claim 1. The fact that ICI might have sought to amend claim 4 is not relevant. It did not do so. What Crennan J called the narrow question simply never arose before, and was not considered by, Branson J. This explains the apparent contradiction between the approach to novelty taken in relation to Application 654176, on the one hand, and Application 658005 on the other, in the same set of reasons. When Branson J focused upon the refrigerant aspects of claim 4, she approached the issue in the same way and reached the same conclusion in substance as that later reached by Crennan J. If Du Pont's analysis were correct, the inconsistency between the two approaches by Branson J would be startling. Furthermore, it would be surprising if Branson J and the Full Court had dealt with the question of novelty of claim 4 of Application 658005 in the pre-emptory way that they respectively did if it had been considered as an independent claim. It is most unlikely that either would have disposed of the question without even noticing or discussing the issues which would clearly arise in that event, as exemplified by the decision of Branson J in relation to Application 654176 and Crennan J in relation to the Divisional Application in suit here. 29 As there is no identity between any issue found by Branson J, confirmed by the Full Court, on the one hand, and any issue for determination in the present application, on the other, there can be no issue estoppel (Kuligowski v Metrobus (2004) 220 CLR 363 at [21], [40]-[54]). 30 I cannot see that the questions raised by Du Pont as to the propriety of the filing of the Divisional Application by ICI have any relevance to establishing the issue estoppels pleaded. 31 The proceeding should be dismissed. The applicant is to pay the costs of the respondents. I certify that the preceding thirty-one (31) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justice Gyles.

Associate: Dated: 31 October 2006 Counsel for the Applicant: Mr IM Jackman SC, Mr PW Flynn

Counsel for the First Respondent: Mr DK Catterns QC, Mr C Dimitriadis

Solicitor for the First Respondent: Phillips Ormonde & Fitzpatrick

Counsel for the Second Respondent: Ms KJ Howard SC

Solicitor for the Second Respondent: Australian Government Solicitor

Dates of Hearing: 16 and 17 October 2006

Date of Judgment: 31 October 2006