AMERICAN HOME PRODUCTS CORPORATION
[1994] APO 58
•28 September 1994
official notice
decision of a delegate of the commissioner of patents
Application : No. 16397/92 in the name of AMERICAN HOME PRODUCTS CORPORATION
Title: Process and intermediates for making isoquinoline derivatives
Action: Hearing in relation to objections during examination
Decision: Issued .
Abstract: Requirements for novelty and inventive step of compounds per se discussed.
Novelty of compounds assessed by considering:
- was the citation published before the priority date of the application under examination;
- what are the essential features of the invention as claimed;
- what is disclosed by the citation (what is clearly and unmistakably disclosed, and does the disclosure enable the preparation of the compounds); and
- is the application a selection?
Claims to intermediate compounds found to possess an inventive step but to be not novel.
patents act 1990
decision of a delegate of the commissioner of patents
Re:Patent Application No. 16397/92 by American Home Products Corporation, and objections raised by the Commissioner during examination.
background
Patent application 16397/92, which is entitled "Process and intermediates for making isoquinoline derivatives" was filed on 20 May 1992. The applicant and nominated person is American Home Products Corporation. The application claims priority from a United States application (having a priority date of 22 May 1991) and a United Kingdom application (having a priority date of 8 April 1992).
A first examination report, raising only the issue of novelty, was issued on 2 August 1993. This objection was maintained in the light of argument from the patent attorney for the applicant. After the third adverse report, the applicant requested a hearing. The applicant was then notified (in a fourth adverse report) that there was also an inventive step objection.
The hearing was held in Canberra on 1 July 1994. The applicant was represented by Mr Paul Kilborn (patent attorney of Phillips Ormonde & Fitzpatrick, Melbourne).
the specification
The specification commences with the statement:
"The present invention relates to a process for the preparation of spiro[isoquinoline-4(1H),3'-pyrrolidine]-1,2',3,5'(2H)-tetrones which are useful as aldose reductase inhibitors. The invention also relates to novel intermediates useful in the process."
The admitted prior art reveals that spiro-isoquinolinepyrrolidines are known to be useful as aldose reductase inhibitors. The problem addressed by the specification is to improve the yield for the preparation of spiro-isoquinoline-pyrrolidines.
The specification relates specifically to a process for the preparation of compounds having the formula:
(II)
in which R1 is hydrogen or halogen and R2 is methyl or dihalogen-substituted benzyl.
The compounds of formula (II) are prepared by the following process:
The specification ends with 15 claims. The key claim is claim 10, which reads as follows:
"10.A nitrile having the formula
(IV)
wherein R1, R2 and -CO2R3 are as defined in claim 1."
The variables R1, R2 and -CO2R3 are defined in claim 1 in the following terms: "R1 is hydrogen or halogen and R2 is methyl or dihalogen-substituted benzyl", and "-CO2R3 is an ester group".
Claims 11, 12, and 15 are appended to claim 10. They read as follows:
"11. A nitrile as claimed in claim 10, wherein R1 and R2 are as defined in claim 4.
12. A nitrile as claimed in claim 10 or 11 wherein R3 is methyl."
"15. A nitrile as claimed in claim 10, substantially as described herein with reference to the Examples."
Claim 4 defines R1 and R2 in the following terms: "R1 is fluorine and R2 is (4-bromo-2-fluorophenyl)methyl".
The specification admits that European patent specification number 0 365 324A discloses a class of nitriles which includes the formula (IV).
the objections
A novelty objection was raised against the invention defined by claim 10 in the light of Australian patent application number 42983/89 (since given the number 617541) in the name of American Home Products Corporation (this document is the Australian equivalent of the admitted prior art document EP 0 365 324A). The citation was laid open to public inspection on 26 April 1990.
The examiner based the objection on the disclosure of a generic formula, called formula (N).
An inventive step objection was also taken against claim 10 in the light of formula (N).
submissions
Mr Kilborn's submissions can be summarised as follows:
-the compounds of claim 10 are novel in the light of the citation. The citation does not provide the necessary degree of disclosure of compounds of formula (N). Cases relevant to the degree of disclosure needed to render a claim not novel are:
"Shell" Refining and Marketing Coy Ld's Patent [1960] RPC 35
E.I. Du Pont de Nemours & Co (Witsiepe's) Application [1982] FSR 303
Flour Oxidizing Company Ld v Carr & Co Ld (1908) 25 RPC 428
These cases establish a requirement for a citation to disclose that a compound has been made in order to anticipate a later application.
There are no examples of compounds of formula (N), and no subgenera of formula (N) are indicated in the citation. Formula (N) does not disclose any compounds.-the present situation does not need to be treated as a selection situation, as the compounds are chosen for a new use not disclosed in the prior art. The authority for this is Auster Ltd v Perfecta Motor Equipments Ld (1924) 41 RPC 482, which is referred to in Patents for Inventions (fourth edition) by T.A.Blanco-White at page 121. It is not necessary to satisfy the classical selection requirements in this situation.
This principle has been applied in prior claiming cases: Westinghouse Electric Corporation (Frost's) Application [1973] RPC 139.
The UK Patent Office Manual of Practice (dated August 1975), para 7,25, states:"More usually, however, a prior disclosure in general terms embracing a number of possible alternatives is no more than a mere suggestion that any of the members, as well as those specifically exemplified, might be used. The problem then becomes one of deciding whether or not subject-matter is clearly and completely absent from the applicant's alleged invention which is a selection (made consciously or unconsciously) of one or more of the members for a particular specified purpose. In practice, if the purpose for which the applicant has selected his members is a purpose not disclosed in the antecedent document, or if his selected members are said to possess specified advantages (or to avoid specified disadvantages) and the statement is not on the face of the documents incorrect, it is not possible to say that an inventive step is clearly lacking, and no objection will be raised or proceeded with under Section 7."
-if it is necessary to consider selection, then the invention claimed by claim 10 represents a selection from the prior art. The compounds possess the advantage that they have utility in forming compounds of formula (II). The compounds of formula (II) are superior pharmaceuticals.
-the inventive step of the invention claimed by claim 10 lies in the fact that the intermediates make possible the new process for preparation of compounds of formula (II).
The test for obviousness is the "Cripps Question" referred to in Sharpe & Dohme Inc v Boots Pure Drug Company Ld (1928) 45 RPC 153 at 173. Also relevant are Wellcome Foundation Ltd v V.R. Laboratories (Aust) Pty Ltd (1981) 148 CLR 262 and Minnesota Mining & Manufacturing Co v Beiersdorf (Australia) Ltd (1980) 144 CLR 253. Ex post facto analysis is not permitted: Meyers Taylor Pty Ltd v Vicarr Industries Ltd (1977) 137 CLR 228 and Palmer v Dunlop Perdriau Rubber Co Ltd (1937) 59 CLR 30.
The problem formulated by the examiner incorporates the solution, which is not proper (European Patent Office decision T137/90).
Decisions of the European Patent Office provide guidance on how to approach the question of the inventive step of chemical intermediates. Relevant decisions are:
Decision T22/82 (BASF/Bis-epoxy ethers) (1982) OJ EPO 341
Decision T163/84 (BAYER/Acetophenone derivatives) (1987) OJ EPO 301
Decision T648/88 (BASF/R,R,R-Alpha-tocopherol) (1991) OJ EPO 292
The production of compounds of formula (II) can be achieved in higher overall yield by using compounds of formula (IV) than using the method exemplified in the citation. The process in the application under examination would not have been expected to work because it would not have been expected that the nitrile could be selectively hydrolysed in the presence of the ester.
decision
There are two issues to be considered in this decision: novelty and inventive step. It is settled law that the two objections are essentially distinct from each other (R D Werner & Co Inc v Bailey Aluminium Products Pty Ltd (1989) 85 ALR 679), and consequently they must be analysed separately.
Issue 1: Novelty
The present case involves the novelty of a claim to a compound in the light of a generic disclosure. I am not aware of any Australian cases involving the application of the reverse infringement test for novelty to this situation. In the absence of such authority, it is necessary for me to review the available law to determine how to handle this issue.
1. Patents relating to compounds: Some general comments
a) Terminology
The term "compound" has many meanings in the dictionary. I will use the term in the chemical sense of a substance composed of two or more elements chemically united in fixed proportions.
In this decision I am specifically concerned with organic compounds. For simplicity I will not use the descriptor "organic" throughout the text, but the decision should be understood in that context.
b) The difference between compounds and formulae
In considering patents relating to compounds, it is important to appreciate the difference between the compound, and the structural formula of the compound. The compound is the actual material (i.e. the thing that you can put in a bottle). The structural formula is an abstract representation of the compound, in the same way that a written word is a representation of an actual thing. However, a structural formula is also a pictorial representation of the arrangement of the atoms that make up a molecule of the compound. It conveys to the informed reader a great deal of information relating to the chemical properties of the compound.
It is possible to produce a precise structural formula for a compound that has never been prepared (provided the formula is constructed in a way that obeys the known rules of chemistry). Thus, every compound has a formula, but every formula does not necessarily have an existing compound.
c) Compounds as inventions
A compound is not a manner of manufacture unless there is a commercial use for the compound (a compound without a use is a mere discovery). It is well known that the properties of compounds cannot be readily predicted merely from a knowledge of the structural formula (this was at the heart of cases such as May & Baker Limited v Boots Pure Drug Company Limited (1950) 67 RPC 23). The thing that makes a new compound into an invention is the identification of a commercial use, or a potential commercial use. The use does not have to be included in the claim, so long as it is described in the specification.
2. The test for novelty
When considering novelty, it is not relevant whether we are considering a compound, or a machine for making aluminium ladders. The same principles apply.
The statutory provisions relating to novelty are sections 7(1) and 18(1)(b) of the Patents Act. Section 7(1) (and the definitions in the Schedule) identifies the prior art base for considering novelty. The relevant prior art base for the purposes of this decision is single documents that have been made publicly available. The relevant date for considering novelty is the priority date of the claim (section 18(1)(b)).
The test for novelty is the reverse infringement test. The classic formulation of this test is that given by Aickin J in Meyers Taylor Pty Ltd v Vicarr Industries Ltd, supra, at page 235: "The basic test for anticipation or want of novelty is the same as that for infringement and generally one can properly ask oneself whether the alleged anticipation would, if the patent were valid, constitute an infringement". This requires the alleged anticipation to disclose all the essential features of the invention as claimed (see Nicaro Holdings Pty Ltd v Martin Engineering Co (1990) 16 IPR 545 at page 549).
The degree of disclosure of the essential features by the alleged anticipation was described by Parker J in Flour Oxidizing v Carr, supra, at page 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."
A more recent formulation of this test was given by the Court of Appeal in The General Tire & Rubber Company v The Firestone Tyre and Rubber Company Limited [1972] RPC 457 at pages 485 to 486:
"If the prior inventor's publication 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 patent, the patentee's claim will have been shown to lack the necessary novelty, that is to say, it will have been anticipated. ... if carrying out the directions contained in the prior inventor's publication will inevitably result in something being made or done which, if the patentee's patent were valid, would constitute an infringement of the patentee's claim, this circumstance demonstrates that the patentee's claim has in fact been anticipated. ... To anticipate the patentee's claim the prior publication must contain clear and unmistakeable (sic) directions to do what the patentee claims to have invented"
A citation must provide a clear and unmistakable disclosure of the essential features of the invention as claimed. This means that I must determine the essential features of a claim to a compound, and what amounts to a clear and unmistakable disclosure when the disclosure is a generic formula.
3. Essential features of a claim to compounds
When a claim is directed to a compound (or a number of compounds) having a specific structural formula (or formulae), an essential feature of the invention claimed is a compound, and not just a formula.
The compound must be characterised in some way, and these characterising features are features of the invention. The structure is the most convenient means of characterising a compound. In cases where the structure of a compound is not known, the compound will be characterised by some other information, such as the method of preparation or physical properties.
Where a compound is characterised by a structural formula, the next question is whether all structural features are essential to the invention as claimed. One possibility is that there can be structural features that do not materially affect the activity of the compound, and are thus not essential features. Normally the activity of a compound cannot be predicted from its structure, so it is not possible to say whether any part of the structure does not materially affect the desired activity. The alternative is that a structure should be regarded as a combination in the patent sense: "the combination of a number of known integers which work in relation to one another so as to produce a new or improved result" (Populin v HB Nominees Pty Ltd (1982) 41 ALR 471 at page 475). For instance, each of the radicals in the structure is known, but the arrangement of the radicals into the structure results in something more than the sum of the radicals that make it up. In such a case, all structural features would be essential.
As a matter of principle, I believe that it is possible that there can be inessential parts of a structure, but that this would not normally be the case. In the examination of an application it is safer to start with a presumption that all the features of a structure are essential, and displace that presumption only on the basis of a sound argument.
The use for a compound is not a feature of a claim to the compound per se. However, as I stated previously, the use for a compound is the thing that makes a compound into an invention, and this use is normally not obvious from the structure. It might be expected that the feature critical to the possibility of an invention is an essential feature of the invention. However, the cases do not support a conclusion that a feature not found in the claims is a feature of the invention as claimed. The use for a compound is thus not an essential feature of such a claim.
There are thus two parts to the essential features: compound, and structure or other characterising information (but noting that not all of the structure may be essential).
4. Disclosure by a generic formula
The central issue is what degree of disclosure by a citation containing a generic formula constitutes a clear and unmistakable disclosure of a compound, and thus represents an anticipation. There is a body of law on chemical selection patents, and a smaller body of law on chemical non-selection patents. I will examine the two separately because I conclude from these cases that a different degree of disclosure is required by the two situations.
5. Degree of disclosure needed to anticipate non-selection patents
The cases on this point are not consistent. In order to determine the current position of the law, I will summarise the non-selection case law chronologically.
a)In Gyogyszeripari Kutato Intezet's Application [1958] RPC 51 (the GKI case) at page 52, Lloyd-Jacob J accepted that a compound is anticipated if a citation "states, explicitly or implicitly, that the compound has been made."
No authorities were referred to in the decision.
b)In Smith Kline & French Laboratories' Application [1968] RPC 415 (the SKF case) at page 425 Lloyd-Jacob J referred to the GKI case and reconfirmed that there is no novelty "if existence has been disclosed in some prior publication."
c)The GKI and SKF cases were the basis of the decision of the New Zealand Supreme Court in Beecham Group Ltd v Bristol-Myers Company (No 2) [1980] 1 NZLR 192. At page 218 of the report Barker J accepted that:
"anticipation requires:(i) A clear specification in the earlier document of the compound claimed in the latter;
(ii) An implicit or explicit statement in the earlier document that the compound in question has in fact been made; and
(iii)That the compound has in fact been made or else instructions had been given in the cited document on how to make it."
In the appeal of this decision to the Court of Appeal (reported as Beecham Group Limited's (New Zealand/Amoxycillin) Application [1982] FSR 181), the matter was decided on selection grounds.
d)The Australian Patent Office adopted the Beecham v Bristol-Myers approach in Bristol-Myers Company v L'Oreal (1989) 16 IPR 652 (see page 657).
e)In Genentech Inc.'s (Human Growth Hormone) Patent [1989] RPC 613, Falconer J considered that the reasoning provided in the SKF case was not satisfactory (see page 633, lines 25 to 29).
In discussing the passage from General Tire v Firestone, supra, dealing with clear and unmistakable directions, the judge stated that "that language seems to postulate an enabling disclosure as a requisite to constitute an anticipation" (page 630 of the report). The judge decided that in order to constitute anticipation of a claim to a new chemical compound, the disclosure in a prior document must be an enabling disclosure (see page 633).
f)In Pall Corp. v Commercial Hydraulics (Bedford) Ltd [1990] FSR 329, Falconer J summarised his decision in Genentech's Patent, supra, in the following terms (at page 347):
"However, in a recent decision of my own in the case of Genentech's Patent (Ch. 1986 G.21441) (not yet reported but made available to Counsel in this case), in which the claimed invention in the claims in issue and alleged to be anticipated was a biochemical compound, I had to consider what is required of a piece of prior art, in that case prior published documents, for it to have made available to the public the invention claimed in such a claim. I held that what is commonly referred to as an enabling disclosure, that is to say, one sufficient in the case of a claim to a chemical compound to enable those skilled in the art to make the compound claimed, was required to make the claimed invention available to the public and so to anticipate it."
g)In Asahi Kasei Kogyo KK's Application [1991] RPC 485 the House of Lords approved Falconer J's decision in Genentech's Patent, supra, and disapproved the decisions in GKI and SKF:
"For my part, it is to me clear that, for anticipation under subsection (2), published information requires to contain an enabling disclosure and that, to this extent at least and contrary to the views expressed in the Court of Appeal, Falconer J.'s decision in Genentech is to be preferred to the decision in the G.K.I. case."
(per Lord Oliver of Aylmerton at page 539)
It seems to me that the House of Lords has approved a change in English patent law from a requirement that the compound be made to a requirement that there be an enabling disclosure. In the absence of clear Australian authority, I believe that I should respect the views of the House of Lords in Asahi's Application, supra, rather than follow the GKI and SKF cases (and decisions based thereon).
Thus clear and unmistakable directions with regard to a compound in a non-selection patent do not require that the compound has been made, but there must be sufficient information to enable the compound to be made.
6. Degree of disclosure needed to anticipate selection patents
The majority of the decided cases on the novelty of chemical inventions have involved the issue of selection.
It is well settled that where a claim to a compound satisfies the selection criteria, the compound will only be anticipated if a citation reveals that the compound has actually been made previously: "the selected compounds have not been made before, or the patent would fail for want of novelty" (I.G. Farbenindustie (1930) 47 RPC 289 at page 321). This requirement has been restated on many occasions (for example, see Beecham Group Ltd v Bristol Laboratories International S.A. [1978] RPC 521 at page 579; Beecham Group Limited's (New Zealand/Amoxycillin) Application, supra, at page 189; E.I. Du Pont de Nemours & Co (Witsiepe's) Application, supra, at pages 309 to 312).
7. Should selection and non-selection patents require the same degree of disclosure?
The requirement for the anticipation of a non-selection patent appears to differ from that for a selection patent. However, I am aware that the contrary view was indicated in "Shell"'s Patent, supra. Lord Evershed MR, delivering the judgement of the Court of Appeal, stated at page 54:
"we feel bound to say that, as at present advised, we are not satisfied of the justification for any different standard of the degree of disclosure in 'selection' cases from that ordinarily applicable; and we think, therefore, that the whole question - including that of the limitation on the power to allow amendment - deserves further consideration upon an appropriate occasion."
The Court was clearly of the view that as a matter of principle the degree of disclosure in selection cases should be the same as for non-selection cases, but declined to decide the matter.
There is also support for the alternative point of view that selection patents occupy a special position in the law of novelty. For instance, in discussing "the degree of rigour with which the alleged anticipation is to be tested", Gummow J (in Nicaro Holdings v Martin Engineering, supra, at page 561) said: "As is illustrated by the discussion of the English authorities by Falconer J in Genentech Inc's (Human Growth Hormone) Patent [1989] RPC 613 at 629-33, selection patents may require special attention, but this is a matter for another day". In the article "Selection Patents" by R.Gupta in Patent World, 1993, 15 it is argued that selection patents are really an anomaly developed to deal with the intrinsic difficulties of chemical patents. I am forced to agree that selection, as it has evolved, is an anomaly.
A selection patent will only be anticipated by a specific disclosure of a compound. A non-selection patent can be anticipated by a disclosure which is both clear and unmistakable, and enabling. A higher degree of disclosure is needed to anticipate a selection patent.
8. The approach to anticipation by a generic formula
When a citation contains a generic formula that encompasses the formula of compounds claimed in a later application, I conclude that the reverse infringement approach to novelty should be as follows:
-was the citation published before the priority date of the application under examination;
-what are the essential features of the invention as claimed;
-what is disclosed by the citation
. what is clearly and unmistakably disclosed.does the disclosure enable the preparation of the compounds; and
-is the application a selection?
It has been suggested that the issues of clear and unmistakable disclosure and enabling disclosure are a single issue: "the 'clear and unmistakable directions' must amount to an enabling disclosure" (Quantel Ltd v Spaceward Microsystems Ltd [1990] RPC 83 at page 112). I feel that there are two issues to be considered, and while it may be possible to include both of them under the one heading, it is conceptually easier to consider them separately.
I will now elaborate on the key issues before proceeding to apply the law to the facts of this case.
a) What compounds are clearly and unmistakably disclosed by a generic formula?
It follows from my conclusion on essential features that there must be a clear and unmistakable disclosure of the relevant compounds, rather than a disclosure of the formula or the use for the compounds.
A generic structural formula represents all the specific structural formulae encompassed by the generic formula. This can be described as the intellectual content of the structural formula. (In F. Hoffman-La Roche & Co. AG v Commissioner of Patents (1970) 123 CLR 529 Gibbs J seems to have reached this conclusion at pages 541 to 542 of the report) The question of what compounds are clearly and unmistakably disclosed is equivalent to what technical information would the citation make public to the instructed reader (though not necessarily revealed in every detail). In Ethyl Corp. v Commissioner of Patents (1969) 39 AOJP 2860, McTiernan J concluded that the use of a broad chemical term in a citation did not disclose all things that fell within the scope of that term: "the term 'aromatic gasoline components' in the earlier specification may but does not necessarily include methyl benzenes or methyl substituted benzenes".
The compounds that are technically disclosed by a specification containing a generic structure will depend on the specific facts of the case. The matters that will have to be considered in this regard cannot be reduced to a simple check-list. However, I consider that the views expressed in Bristol-Myers v L'Oreal, supra, at page 657, are instructive:
"I do not think the proper approach is to consider that the generic formula in US patent No 3037057 discloses all the structural formulae which a gorilla might derive by choosing any of the substituents and by choosing any substitution pattern of the benzene ring. Rather I think the generic formula has to be considered in conjunction with the compounds specifically described in the citation in order to determine which combinations of substituents, and which substitution patterns are disclosed in the citation."
See also the analysis in Genentech's Patent, supra, at pages 639 et seq. Although this analysis is under the heading of enabling disclosure, the discussion includes the question of what compounds were disclosed by the citation.
b) Does the disclosure of the citation enable the production of the compounds whose structures have been disclosed?
The information necessary to enable the production of a compound can be summarised as follows:
.the sufficiency of the information is assessed by the person skilled in the art (Quantel v Spaceward Microsystems, supra, at page 108);
.it is not necessary for the compound to have been made or tested (Genentech's Patent, supra, at page 632);
.it may be necessary to carry out some routine trial and error (C Van Der Lely NV v Bamfords Ltd [1963] RPC 61 at pages 71 to 72);
.a claim on its own can give sufficient information (Genentech's Patent, supra, at page 632);
.a mere statement of the existence of a compound is insufficient unless the method of preparation is self-evident (Asahi's Application, supra, at page 539); and
.since an error in a citation is not a disclosure, if the method given appears to be in error (i.e. does not appear to be technically credible to a person skilled in the art), then a preparation has not been disclosed.
I conclude that an enabling disclosure is provided if a generic preparative method is given in a citation or is self-evident, and this method would have been considered to be technically credible by a person skilled in the art at the date of publication of the citation.
c)Is there a selection?
If a citation contains clear and unmistakable directions and an enabling disclosure, then the application will prima facie lack novelty. Then, and only then, will it be necessary to consider the question of selection.
The critical issue in selection is whether the selection criteria can be satisfied. The criteria are:
"First, a selection patent to be valid must be based on some substantial advantage to be secured by the use of the selected members. (The phrase will be understood to include the case of a substantial disadvantage to be thereby avoided.) Secondly, the whole of the selected members must possess the advantage in question. Thirdly, the selection must be in respect of a quality of special character which can fairly be said to be peculiar to the selected group." (I.G. Farbenindustie A.G.'s Patents, supra, at pages 322 to 323)
These criteria have been explained and expanded in a number of reported decisions. For the present decision, it is only necessary for me to mention Bristol-Myers Company v L'Oreal (1988) AIPC 90-529. At page 38,551 the hearing officer stated "A requirement for a selection patent is the discovery that one or more members of a previously known class of products possess some special advantage for a particular purpose, which could not be predicted before the discovery was made (Beecham Group Ltd v Bristol Laboratories International SA (1978) RPC 521 at p 579)."
Where selection is established, there is only a lack of novelty if the selected compounds have previously been made. The clearest evidence that a compound has been made before is provided if the compound is one of the worked examples of the invention.
9. The decision in Auster v Perfecta
I was referred to the decision in Auster v Perfecta, supra, as authority for the proposition that where a selected group is put to a new use or application not referred to in the earlier disclosure, the case is not really one of selection. The relevant part of the decision is at page 497:
"The only other point taken by the Defendants on this branch of the case to which I need refer, is that the invention claimed by Auster was a mere selection among possible alternatives within the meaning given to that phrase by Lord Parker in the case of Clyde Nail Company v Russell ... In my opinion, neither the actual decision in the Clyde Nail Company's case, nor the principle there enunciated by Lord Parker, has any application to the present case ... Auster does not claim to have selected a particular device among several alternatives for use in a known process; what he claims is a particular device for carrying out a novel idea, which is an altogether different proposition."
To my knowledge, the Auster decision is only referred to in one decision published in the Reports of Patent Cases (British United Shoe Machinery Co., Ld v Gimson Shoe Machinery Co., Ld (1928) 45 RPC 290). The Auster decision is referred to on page 301 of the report in the context of obviousness of a combination. Lawrence LJ stated: "I will not repeat what I said in Auster Limited v Perfecta Motor Equipments, Limited ((1924) 41 RPC 482), as to the difficulty of deciding the question of subject-matter in a case where the invention consists of a new apparatus composed of known elements." In the light of the BUSM case, I consider that the Auster case stands for the proposition that a new combination of known integers for a purpose not previously suggested is not obvious, and selection is not necessary in order to avoid an allegation of lack of inventive step. I accept this proposition. The test for selection remains the I.G. Farbenindustie test.
Mr Kilborn referred to the fact that some prior claiming cases used the approach that a different use is not a selection. The law on prior claiming was based on a number of different tests. "None are entirely satisfactory, conclusive or universally applicable" (Westinghouse Electric Corporation (Frost's) Application, supra, at page 144). I do not think that the law on prior claiming is helpful to me in the present case.
The practice stated in the UK Patent Office Manual referred to by Mr Kilborn seems to support a conclusion that, in a selection situation, the presence of an inventive step will automatically infer novelty. I note from the photocopy of paragraphs 7,1 to 7,49 provided by Mr Kilborn that the pages are dated August 1978, and that para 7,25 of the Manual cites as its only authority the "Shell" Patent case, supra. While I note this practice, I believe that I must apply the law derived from the reported cases.
10. Application of the law to the facts
a) Publication details
The citation (AU 617541) was published in Australia on 26 April 1990. The earliest priority date of the application under examination is 22 May 1991. Thus the citation is part of the relevant prior art base.
b) Essential features of claim 10
There are two parts to the essential features: compound and structure.
When considering the structural formula (IV), I begin with the presumption that all parts of the structure are essential features of the invention. Mr Kilborn submitted that the group R3 is not an essential feature of the structure because the nature of R3 is immaterial to the cyclisation reaction. In the present case it is apparent that the group -OR3 is a leaving group in the cyclisation. The nature of R3 would be expected to have very little effect on the leaving group ability of -OR3, so the nature of R3 is probably not essential to the cyclisation. It seems to me that the nature of the R3 group is probably not material to the use of the compound for cyclisation. However, since R3 is defined as any ester forming group, this definition is effectively the same as finding that R3 is not an essential feature of the invention. For simplicity, I will consider R3 as an inessential feature.
c) The citation
The citation relates to spiro-isoquinoline-pyrrolidine tetrones and analogues of the formula:
(I)
wherein the values of the variables are:
"R1 and R2 are independently hydrogen, alkyl containing 1 to 6 carbon atoms, halogen, lower alkoxy containing 1 to 6 carbon atoms, trifluoromethyl, lower alkylthio wherein lower alkyl contains 1 to 6 carbon atoms, dialkylamino wherein alkyl contains 1 to 6 carbon atoms, nitro, aryl, or aryl (lower alkyl) oxy wherein aryl contains 6 to 10 carbon atoms and lower alkyl contains 1 to 6 carbon atoms; R3 is hydrogen lower alkyl containing 1 to 6 carbon atoms, aryl (lower alkyl) or halogen substituted aryl (lower alkyl) wherein aryl contains 6 to 10 carbon atoms and lower alkyl contains 1 to 6 carbon atoms, acyl or heterocyclic (lower alkyl) of the structural formula
wherein R4 is lower alkylene containing 1 to 3 carbon atoms; X is lower alkylene containing 1 to 3 carbon atoms, oxygen, sulfur or NH; Y and Z are independently oxygen or sulfur, M and W are independently carbonyl, thiocarbonyl, sulfonyl, sulfoxo or lower alkylene containing 1 to 2 carbon atoms with the proviso that M and W are not both lower alkylene when X is nitrogen, or a pharmaceutically acceptable salt thereof."
The compounds of formula (I) are stated to be useful as aldose reductase inhibitors.
Several methods of preparing compounds of formula (I) are described in general terms. One method involves the use of compounds of the formula:
(N)
The citation describes the use of compounds of formula (N) to produce a subset of the compounds of formula (I) by the following process:
The specification does not exemplify any compounds of formula (N), nor are there any references to preferred subgenera of formula (N). Compounds of formula (G) are exemplified, and are used to prepare compounds of formula (I) by different processes. None of the compounds of formula (I) exemplified possess a thiocarbonyl in the pyrrolidine ring.
d) What compounds are clearly and unmistakably disclosed by the citation?
It is not contested that formula (I) of the citation includes formula (II) of the application, and that formula (N) of the citation includes the formula (IV) of the application (but also includes many other formulae).
The instructed reader would understand from formula (N) alone what structures it represents. Formula (N) is a shorthand representation of all the individual structural formulae within the scope of the generic formula (by my reckoning, in excess of 100,000,000 formulae). There is no ambiguity as to the intellectual content of formula (N). The question is which of the compounds are technically disclosed by the citation.
The factors that indicate that compounds of formula (IV) are not technically disclosed are:
i) There are no examples of compounds of formula (N); and
ii) There are no preferred subgenera of formula (N) listed in the citation.
The factors that indicate that compounds of formula (IV) are technically disclosed are:
iii) Formula (N) is clearly disclosed in general terms;
iv) The starting materials for preparing compounds of formula (N) (i.e. compounds of formula (G)) are exemplified. Five of the seven examples of compounds of formula (G) are compounds that would form compounds of formula (IV) if reacted with BrCH2CN. Three of these compounds are actually used to prepare compounds of formula (IV) in the application under examination. [I note without comment that the spectral and analytical data for these three compounds in the citation is not the same as in the application under examination];
v) The statement of the values of the variables in the citation is a precise disclosure with regard to some values of the variables, but not precise with regard to others. The statement of the variables (on its own) is a precise disclosure with regard to the following values
. R1 and R2 = hydrogen
. Y and Z = oxygen
. M and W = carbonyl; and
vi) The compounds of formula (I) that are exemplified in the citation contain the variables M, W, R1, R2, R3 and n (which also occur in formula (N)). The variables that are represented in the examples form a narrow group. A comparison of the variables as exemplified in formula (I) and as their equivalents appear in formula (IV), is as follows
Variable Exemplified in formula (I) Formula (IV)
M carbonyl carbonyl
W carbonyl carbonyl
R1 H, 6-F, 6-Cl, 6-Br, 5-F H, 6-halogen
R2 H, 7-F, 7-Cl, 7-MeO, 8-F H
R3 Me, Et, Pr, Bu, Me, dihalobenzyl
3,4-Cl2-benzyl,
4-Br-2-F-benzyl
n 1 1
I do not believe it would be proper to simply mosaic the variables exemplified. However, it is essential to consider the range of variables exemplified in order to understand what the specification would disclose to an instructed reader. In this case the examples demonstrate that the citation is actually concerned with compounds having variables matching those in formula (IV).
The question that I must answer is what technical information does the citation make public to the instructed reader (though not necessarily revealed in every detail). On the one hand, formula (N) generally discloses a class of compounds. The starting materials for preparing compounds of formula (N), i.e. compounds of formula (G), are specifically disclosed, and the examples are predominantly of the type that would produce compounds of formula (IV). The exemplification of variables indicates that the substitution pattern in formula (IV) is preferred. On the other hand, there are no specific examples of compounds of formula (N).
The absence of a specific example is significant, but not determinative of the question of disclosure; it is necessary to consider whether the other factors, taken as a whole, are sufficient to constitute a disclosure. I consider that a reader of the citation would have considered that it had been made public that compounds of formula (N) having the substitution in formula (IV) are suitable for preparing spiro-isoquinoline compounds via thioamides of formula (D).
e) Does the disclosure of the citation enable the production of the compounds whose structures have been disclosed?
A generic method of preparing compounds of formula (N) is described. This method is technically credible, and is in fact the method that was used in the application under examination. I conclude that the disclosure in the citation would enable the production of compounds of formula (N).
f) Is there a selection?
While selection was not relied upon by Mr Kilborn, it was advanced as an approach which could be applied in the present case. As there are no examples of compounds of formula (N) in the citation, the invention is novel if the application is a selection.
The advantage was stated to be that the compounds of formula (IV) allowed the preparation of compounds of formula (II), which are superior pharmaceutical agents. A table of experimental results showing the superior lowering of dulcitol accumulation in vivo by compounds of formula (II) was provided in a letter in response to the examiner's first report. There may well be an advantage possessed by the compounds of formula (II), but the compounds of formula (II) are specifically disclosed by the citation (examples of compounds of formula (II) are given at pages 79, 81, 87, 98, 99, 100 and 101 of the citation). The compounds of formula (II) are not themselves patentable, but can their properties be the basis for a selection of compounds of formula (IV)?
I must now consider whether there is an unexpected advantage possessed by the compounds of formula (IV). The property of the compounds of formula (IV), i.e. that they have the correct variables to produce compounds of formula (II), is not something that could not have been predicted before the discovery of the properties of the compounds of formula (II). It requires nothing more than an understanding of basic organic chemistry to see that formula (IV) is appropriately substituted to produce the substitution pattern of formula (II) on formation of the pyrrolidine ring. Consequently, I do not believe that this property provides a basis for a selection in the present situation.
However, even if I am wrong in this conclusion, there is a further reason why the application is not a selection. The specification does not contain a disclosure of the advantages on which a selection is based. The only reference to the property of compounds of formula (II) that I can find in the specification appears on page 7: "which have strong aldose reductase inhibiting activity and are expected useful (sic) as remedies for diabetic complications". Consequently, the specification does not provide the quid pro quo required for a selection patent (see Beecham Group Ltd v Bristol Laboratories International S.A., supra, at page 579).
An alternative possibility is that the compounds of formula (IV) possess the advantage that they can produce compounds of formula (I) in higher yield than was possible using the prior art method. There is no indication that the ability to produce compounds of formula (I) in higher yield is a property peculiar to the compounds of formula (IV) (the third criterion for selection). Rather, the higher yield results from the new process steps, rather than the starting materials. Consequently, this property does not provide the basis for a selection.
11. Conclusion on novelty
I conclude that the invention defined by claim 10 is not novel when compared to the disclosure in AU 617541. The invention defined by claims 11, 12, and 15 is similarly lacking in novelty.
Issue 2: Inventive step
1. General comments
"The tendency in later decisions this century has been to treat novelty and invention or subject matter as distinct matters ... It must not be forgotten that the two are usually closely connected in patent cases."
(Werner v Bailey, supra at page 687)
Once a claimed invention is not novel, it is a somewhat academic exercise to consider whether there is also an inventive step: the claim cannot stand as it is. However, in the examination process it is possible to amend a specification to attempt to overcome an objection of lack of novelty. In this context it is necessary for me to consider the further question of whether there is a lack of inventive step.
Lack of inventive step does not automatically follow from a lack of novelty (although lack of novelty raises a strong suspicion of lack of inventive step). Although this may seem surprising, it follows inevitably from the fact that the two objections are distinct, and involve different tests. It is necessary to examine the issue of inventive step de novo.
2. The test for inventive step
The statutory provisions relating to inventive step are contained in subsections 7(2) and 7(3) of the Patents Act:
"(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.
[Notes: (1) For the meaning of "document" see section 25 of the Acts Interpretation Act 1901.
(2)See also the definitions of "prior art base" and "prior art information" in Schedule 1: see also paragraph 18 (1) (b) and subsection 98 (1).]"
The definitions of "prior art base" and "prior art information" given in Schedule 1 are as follows:
""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); and
(ii)information contained in a published specification filed in respect of a complete application where:
(A)if the information is, or were to be, the subject of a claim of the specification, the claim has, or would have, a priority date earlier than that of the claim under consideration; and
(B)the specification was published after the priority date of the claim under consideration; and
(C)the information was contained in the specification on its filing date and when it was published;
[Note: For the meaning of "document" see section 25 of the Acts Interpretation Act 1901.]
"prior art information" means:
(a)for the purposes of subsection 7 (1) - information that is part of the prior art base in relation to deciding whether an invention is or is not novel; and
(b)for the purposes of subsection 7 (3) - information that is part of the prior art base in relation to deciding whether an invention does or does not involve an inventive step;"
It follows that there is an inventive step objection if the invention would have been obvious to a person skilled in the relevant art in the light of information in a single document (made publicly available before the priority date of the claim) that could reasonably have been expected to have been ascertained, understood and regarded as relevant to work in the relevant art. This approach clearly differs from the test under the Patents Act 1952 in that under the 1952 Act inventive step was assessed against a prior art base of the common general knowledge (for example, see Minnesota Mining & Manufacturing v Beiersdorf, supra). Although a much larger range of sources of information may be relied upon for determining inventive step under the 1990 Act, the question of what is obvious in the light of that information must still be determined. Cases determined under the 1952 Act are relevant to the specific question of what is obvious (but irrelevant to the question of whether information can be considered; see also Winner v Ammar Holdings Pty Ltd (1993) 113 ALR 63 at page 67).
The approach to the question of what is obvious must involve the concept of the relevant art (which is recurrent in section 7). The reported cases under the 1952 Act establish that obviousness can be determined by considering whether the invention as claimed provides an obvious solution to a problem in the light of the relevant prior art (for example, see Winner v Ammar Holdings Pty Ltd, supra). However, in other cases the problem-solution approach has not been followed (for instance, Elconnex Pty Ltd v Gerard Industries Pty Ltd, (1992) AIPC 90-848). It is not clear whether only one approach is permitted under the 1990 Act, or whether one approach is more suited to chemical inventions. I will use the problem-solution approach because it is clearly consistent with the Act (the problem-solution approach incorporates a consideration of the relevant art), and provides a structured approach for tackling the question of obviousness. When incorporated into the requirements of the 1990 Act, the test for inventive step becomes:
. what is the problem confronted by the application;
.can the information in the document be considered for inventive step purposes
- is it part of the prior art base
-is it reasonable to expect it to have been ascertained, understood and regarded as relevant to work in the art;
.what does the citation disclose; and
.is the solution obvious to the person skilled in the art in the light of the disclosure of the citation.
The formulation of the problem is critical in this approach. I accept Mr Kilborn's submission that the formulation of the problem must not incorporate the solution.
This general method is the same as that discussed in the Manual of Practice and Procedure issued by the Australian Patent Office (see Part 4 of Volume 2). Mr Kilborn stated that he considered the approach in the Manual to be a proper approach to considering inventive step, although there could be other valid approaches. The "Cripps Question" approach advanced by Mr Kilborn is also a problem-solution approach.
3. Obviousness in the light of a generic formula
When does the disclosure of a generic structural formula in a citation render a claim to a compound lacking in inventive step? There has been little opportunity for Australian courts to consider this question because it has never been accepted that a generic formula on its own is part of the common general knowledge.
There are some published decisions of the European Patent Office where obviousness of intermediates in chemical processes has been considered in the light of a published document. These decisions are not part of Australian patent law, and I will not rely on them as a source of the law. (I refer to these decisions in the context of the definition of the problem) I believe that the obviousness of a compound should be assessed in the same way as for other inventions:
"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." (Wellcome Foundation v V.R. Laboratories, supra, at page 286)
4. Application of the law to the facts
a) The problem
The problem addressed by the specification is to provide an improved preparation of known spiro-isoquinoline compounds of formula (II). The exact formulation of the problem may depend on the aspect of the invention that is the subject of a particular claim. Claim 10 is directed to the compounds per se. The problem must be formulated in such a way that the solution is "compounds" and not "process". I also note that compounds do not have a purpose, only a suitability for a purpose (Virbac (Australia) Pty Ltd v Merck Patent GmbH, Federal Court decision, NG 983 of 1992 and NG 985 of 1992, 11 August 1994, unreported; see page 10). Consequently the formulation of the problem should be in the form "to provide a compound suitable for a use".
There are two formulations of the problem that are apparent to me. Firstly, the problem could be "to provide compounds suitable for an alternative method of preparation of compounds of formula (II)". The alternative problem is "to provide compounds suitable for a higher yielding preparation of compounds of formula (II)". [The incorporation of the use of a compound into the problem that is solved by a claim to the compound per se is standard in decisions of the European Patent Office; see for example decision T163/84 (BAYER/Acetophenone derivatives) (1987) OJ EPO 301 and decision T648/88 (BASF/R,R,R-Alpha-tocopherol) (1991) OJ EPO 292] The compounds of claim 10 solve both formulations of the problem. The compounds are suitable for an alternative preparation, and the compounds are suitable for a higher yielding preparation. I believe that the answer to the question of obviousness is the same regardless of the formulation of the problem, so I do not need to choose between the formulations.
I will use as the problem the broader formulation: "to provide compounds suitable for an alternative method of preparation of compounds of formula (II)".
I consider that this problem lies in the art of spiro—isoquinoline synthesis.
b) Can the information in the document be considered for inventive step purposes:
- is it part of the prior art base; and
-is it reasonable to expect it to have been ascertained, understood and regarded as relevant to work in the art
The relevant document (AU 617541) is a single document that was published in Australia before the earliest priority date of the application under examination. Thus the information in the document is part of the prior art base.
In considering whether the information could reasonably have been expected to have been ascertained, understood and regarded as relevant I must keep in mind that this must be assessed in the context of the spiro—isoquinoline synthesis art. The document relates to the preparation of spiro-isoquinoline compounds of a formula that includes formula (II). The document does not seem to be ambiguous or unclear to an organic chemist. The document generically discloses several methods of preparation of spiro—isoquinoline compounds of formula (II), and related compounds, involving a number of different intermediates.
An issue which was not argued is that the document is the admitted prior art that the applicant is trying to improve upon. Could the information in a document relating to the problem be considered as relevant? The information relating to the problem provides background technical information, and in this sense at least it is relevant to work in the art.
I consider that a person skilled in the art could reasonably have been expected to have ascertained, understood and regarded the information in this document as relevant to work in the art. No arguments to the contrary were advanced by Mr Kilborn.
c) What does the citation disclose
I previously found that the citation clearly discloses that compounds of formula (N) having the substitution in formula (IV) are suitable for preparing compounds of the formula:
via thioamides of formula (D). Those products are analogous to formula (II), in that they contain a thiocarbonyl rather than a carbonyl group in the pyrrolidine ring. The citation does not suggest that compounds of formula (N) can be used to prepare end products having a carbonyl group in the pyrrolidine ring.
d) Is the solution obvious in the light of the citation
The question that I must answer is whether it would have been a matter of routine to choose compounds of formula (N) as suitable for an alternative method of preparation of compounds of formula (II). There is no indication in the citation that compounds of formula (N) would be suitable for the preparation of compounds of formula (II), and no basis for concluding that it would be a matter of routine to choose them as suitable for this different (i.e. not disclosed) use. Thus, it is not obvious that they are suitable for an alternative preparation. It also follows that the compounds do not solve the problem of a higher yielding alternative. Thus, because of the limited nature of the disclosure, the compounds per se are not obvious, even though they have been disclosed.
The best that might be said is that the compounds of formula (N) might be included as part of a systematic search for a solution to the problem, but there is no reason that I can see for considering that they would have been regarded as likely to be a solution.
The compounds of claim 10 are not an obvious solution of either formulation of the problem, and are thus not obvious.
5. Conclusion on inventive step
I conclude that the invention defined by claim 10 possesses an inventive step when compared to the disclosure of AU 617541.
conclusion
The invention defined by claim 10 (and also claims 11, 12 and 15) possesses an inventive step but is not novel when compared to AU 617541. Consequently the application does not comply with section 18(1)(b). This deficiency may be readily overcome by amendment. Consequently, I allow the applicant the time remaining for acceptance to propose amendments.
S.D.Barker
Delegate of the Commissioner of Patents
Patent attorneys for the applicant : Phillips Ormonde & Fitzpatrick, Melbourne
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