Almost a year to the day after the landmark decision (X ZR 89/07) of the German Federal Court of Justice (Bundesgerichtshof), the UK Court of Appeal has similarly held Lilly’s so-called selection patent on olanzapine (ZYPREXA) valid over prior art disclosing a genus of compounds covering, but not specifically describing, olanzapine. In doing so, the court drew on EPO jurisprudence, preferring the EPO Board of Appeal approach in such cases to that of UK precedent on selection patents dating back to rules developed in I.G. Farbenindustrie’s Patents (1930) 47 RPC 289.

The I.G. rules comprised three general propositions: First, a selection patent to be valid must be based on some substantial advantage to be secured by the use of the selected members. Secondly, the whole of the selected members must possess the advantage in question. Thirdly, the selection must be in respect of a quality of a special character which can fairly be said to be peculiar to the selected group.

As pointed out by Lord Justice Jacob, rules in the I.G. case about selection patents were formulated under the pre-1977 Patents Act common law, which did not draw a distinction between lack of novelty and obviousness, both of which fell under the general umbrella “lack of subject-matter.” He went on to say that the I.G. rules “form no part of the EPO Guidelines for Examination and no Board of Appeal decision was cited which applied them. So I think the best thing to do is to regard them as part of legal history, not as part of the living law.”

There we have it; the I.G. rules which were almost a special sub-branch of patentability as part of English law before the Patents Act 1977 (to paraphrase Lord Justice Jacob) have no place today in the determination of whether a selection invention is patentable or not in the UK. Rather the correct approach is that of the EPO, which considers inventions, including selection inventions, from the perspective of technical contribution founded firmly around a fundamental question: has the patentee made a novel, non-obvious technical advance and provided sufficient justification for it to be credible?

In its deliberation on technical contribution, the Court considered if, by identifying olanzapine and disclosing its properties, Lilly was making an arbitrary selection. Their answer was a resounding no. The Court stated that the problems identified by the selection patent had nothing to do with selecting from a wider class in the prior art patent. The challenge was to find a compound which avoided the side effects of other structurally related compounds and, the patent did indeed discloses superior properties for olanzapine compared with the closely analogous compound ethyl olanzapine. The Court was also dismissive of the teaching of the prior art stating: “it is also quite clear that the disclosure of 235 would have been read in 1990 with at least a pinch (perhaps a sackful) of salt. All the skilled reader would get from 235 is the rather vague promise of “neuroleptic, sedative or relaxant effects for all 10¹⁹ compounds” with the equally vague promise of “high therapeutic index”.”

Another win for Lilly to add to decisions in Germany and the US upholding the selection patent for olanzapine. Of course, in the deficit column is the decision of the Federal Court of Canada last October holding that Lilly’s Canadian Patent No 2,041,113 was not a valid selection patent.

Of more general import are the concerted efforts of judges of national European Courts to be consistent with EPO jurisprudence and, where possible, with each other. One hopes that such harmonisation at the national Court level will help smooth the path to a unified EU patent litigation system, an initiative firmly on the EU agenda following the EU Council approval in December last of a package of reforms including the formation of an EU patent court.