Merck & Company, Inc. v Pharmaforte Singapore Pte Ltd

• Jurisdiction: Singapore
• Judge: Chao Hick Tin JA
• Judgment Date: 28 July 2000
• Neutral Citation: [2000] SGCA 39
• Citation: [2000] SGCA 39
• Date: 28 July 2000
• Year: 2000
• Plaintiff Counsel: P Sivakumar and Vicki Heng (Ella Cheong & G Mirandah)
• Docket Number: Civil Appeal No 9 of 2000
• Defendant Counsel: Ranvir Kumar Singh and Vivienne Kaur (Kumar & Loh)
• Court: Court of Appeal (Singapore)
• Published date: 19 September 2003

(delivering the judgment of the court):This is an appeal against the decision of Lai Kew Chai J where he dismissed the appellant`s claim against the respondents for patent infringement and held that the products claims in claims Nos 16-21 of the patent in suit are invalid. He also held that the process which the respondents adopted to manufacture their product was different from the process disclosed in claim No 11.

The appellants are one of the largest pharmaceutical companies in the world. They are the registered proprietors of Singapore Patent No 9690405-7 (registered on 15 June 1996), the patent in suit, which relates to a `process for the lactonization of mevinic acids and analogs thereof.` This patent, which comprises both process (lactonization) and product (Lovastatin with a dimeric impurity of less than 0.2%) claims, is derived from the European Patent No 0351918B1 (filed on 17 July 1989 and granted on 14 September 1994) and which in turn claimed priority from the US Patent application No 221475 filed on 19 July 1988 (the priority date).

The respondents are a Singapore incorporated company that import and distribute pharmaceutical products, including a product called `Apo-Lovastatin` which is manufactured in Canada by Apotex Inc, the largest pharmaceutical company in that country. It was the importation of the product, `Apo-Lovastatin`, which gave rise to this action.

The facts

In June 1979 the appellants filed patent applications in the United States and elsewhere on the compound Lovastatin and certain fermentation processes which they had been developing to produce the compound. In that patent, the appellants claimed that their cultivation of a micro-fungus of the genus Aspergillus produced a new compound that was a potent inhibitor of the biosynthesis of cholesterol in humans. The compounds of that invention were useful as anti-hypercholesteremic agents for the treatment of atherosclerosis, hyperlipernia and similar diseases in humans. Those compounds are collectively termed `statins`. Statins are marketed in a form known as the `lactone form`. The lactone is a chemical ring structure and is obtained from the free acid formed by the process of `lactonization`. The process of lactonization results in lactone forming from an intramolecular condensation of the free acid. However, an intermolecular condensation of a pre-formed lactone with another open acid molecule leads to the formation of an inactive dimer. In the past, it was thought that the formation of such dimers could not be completely suppressed. Therefore, dimer impurity in statins in amounts from 0.4 - 0.8% was deemed to be unavoidable.

The patent in this suit, as mentioned above, was first filed in the United States on 19 July 1988. That patent contained claims for a compound made by a specific process which minimize the formation of the dimer impurity when the compound Lovastatin is converted from its open acid form into a lactone form. However, that US patent did not contain a stand-alone product claim. About a year later, on 17 July 1989, the appellants filed an European patent application, claiming priority from the US filing date. The European patent application contained stand-alone product claims to the compound Lovastatin where the dimeric impurity was at a level of less than 0.2%, regardless of the method of manufacture.

This action was instituted by the appellants because they claimed that the product, Apo-Lovastatin, manufactured by Apotex Inc of Canada and imported into Singapore by the respondents possessed dimeric impurity levels of less than 0.2%, and infringed their patent rights. Specifically, they alleged that the respondents have infringed claims 16-21 (the product claims) and claim 11 (the process claim).

The respondents argued that the product claims are invalid because they lack novelty and an inventive step. As regards the process claim, the respondents contended that the process employed by Apotex Inc to produce Apo-Lovastatin was different from the process specified in claim 11. The trial judge upheld all the contentions of the respondents. In coming to the conclusion that the patent was invalid, he found that the appellants` product was not novel. He held that utility is an essential requirement of novelty, and, in this instance there was an absence of utility. He also found that the patent in suit had been anticipated by prior disclosures. He further held that differences in degree of purity of a compound were not patentable, as opposed to differences in the type or kind of compound. As regards the requirement of an inventive step, the trial judge held that the purification of Lovastatin was an obvious step for a person skilled in the art to take.

The appeal

In his submission before us, counsel for the appellants did not pursue the point relating to the process claim as he recognised that that point related to a finding of fact. However, counsel contended that the trial judge was wrong in his findings on both the novelty point as well as the inventive step point.

Utility

The first line of attack of the appellants concerns the element of utility. Counsel submitted that the trial judge erred when he relied upon the irrelevant issue of utility, raised by the respondents, to arrive at his decision that the product claims were invalid. We will now quote what the trial judge said (at [para ] 23):

... a more useful prescriptive test particularly for cases of this kind, within a novelty enquiry, is an assessment of the utility of the patented product. There are no shortage of cases which clearly impose the requirement of utility as a necessary ingredient of patentability notwithstanding its absence as a statutory requirement of novelty.

At this juncture, it is necessary for us to quote the relevant provisions of our Patents Act 1994, which are based on the English Patents Act of 1977:

13(1) Subject to subsections (2) and (3), a patentable invention is one that satisfies the following conditions:

(a) the invention is new;

(b) it involves an inventive step; and

(c) it is capable of industrial application.

80(1) Subject to the provisions of this Act, the Registrar may, on the application of any person, by order revoke a patent for an invention on (but only on) any of the following grounds:

(a) the invention is not a patentable invention:

Under the previous UK law, the Patents Act 1949, a patent could be revoked where [s 32(1)(g)]:

the invention, so far claimed in any claim of the complete specification, is not useful.

In view of the absence of s 32(1)(g) in the 1977 Act (and in our 1994 Patents Act), the appellant argued that `utility` is no more a prerequisite to acquiring a patent under s 13.

The appellants contended that the 1994 Act establishes a completely new code for patents and that it is no longer necessary to establish utility. In this regard, they relied upon Genentech Inc`s Patent [1989] RPC 147 where Purchas LJ explained that the 1977 Act:

provided a complete code dealing with the application for and grant of a patent and thus displaced any residual common law element which previously had been preserved by succeeding statutes.

In Unilever Ltd (Davis`s) Application [1983] RPC 219 Falconer J (at p 229), in answer to the argument that in the absence of clear wording the legislature must be presumed not to have intended to change the law, said:

Parliament made it abundantly clear in the long title to the Act ... that the old law of patents is being swept away.

Basing on the above, counsel for the appellants submitted that what is provided in the 1994 Act is exhaustive and that the earlier English decisions, which viewed the utility of a product to be a relevant factor in the assessment of novelty, and thus patentability, should not be relied upon, it being something swept away by the new law.

We must, however, point out that `inutility` as a ground to revoke a patent was only introduced in the 1949 UK Act. The Patents Act before 1949 did not contain such a provision. Before then, the absence of a provision similar to s 32(1)(g), had never precluded the court from considering the question of `utility` in determining patentability. In Badische Anilin Und Soda Fabrik v Levinstein [1887] 4 RPC 449, the Lord Chancellor expressly addressed the point when he stated (at p 462):

there is certainly authority for saying that an invention must be useful, although that word is not found in the statute ... but it is obvious.

In Welsbach Incandescent Gas Light Co Ltd v New Incandescent (Sunlight Patent) Gas Lighting Co Ltd [1900] 17 RPC 237 the court said:

Utility, in Patent law, does not, as I understand it, mean either abstract utility, or comparative or competitive utility, or commercial utility. It was described by Mr Justice Grare, in Young v Raseulled, in 1st Reports of Patent Cases, page 34, as meaning an invention better than the preceding knowledge of the trade as to a particular fabric. I adopt this definition if the word `better` be understood as meaning better in some respects and not necessarily better in every respect; so that, for instance, an article which is good, though not so good as that previously known, but which can be produced more cheaply by another process, is better in that it is better in point of cost, although not so good in point of quality.

At this point it may perhaps be appropriate to refer to the sense in which the respondents are contending that there is a lack of utility in the subject invention. What the respondents are saying is that Lovastatin with a dimer impurity of less than 0.2% does not have any improved performance or therapautic advantage as compared with existing statins, as an anti-hypercholesteremic agent in the treatment of atherosclerosis, hyperlipemia and like diseases. Lai Kew Chai J ruled that utility was relevant in the assessment of novelty, and thus...