The Court of Appeal has today handed down an important decision in Generics [UK] Limited t/a Mylan ("Mylan") v Yeda Research & Development Co Ltd ("Yeda") & Teva Pharmaceuticals Industries Ltd [2013] EWCA Civ 925. It concerns Yeda's patent for a synthetic copolymer known as copolymer-1. Mylan had sought revocation of the patent and a declaration of non-infringement of their product, copaxone.

The first instance decision that the patent is valid and refusing the declaration of non-infringement has been upheld.

However, although it did not affect the decision, the Court of Appeal differed with the first instance judge, Arnold J, on a point of law that has general application to patents. This is whether evidence that post-dates the priority date of a patent may be used to show that the claimed invention actually made no plausible "technical contribution". If there is found to be no technical contribution it follows that there can be no invention and the patent is invalid. The Court of Appeal has held that such post-dated evidence is admissible. The effect of the decision is that material produced after the priority date of a patent, which shows that the purported technical contribution of the patent does not work or is implausible, may be used in evidence to support a finding of invalidity. An example of such material, as in this case, is clinical trial data, but the principle is not limited to pharmaceutical cases.

The requirement for a patent to have a plausible technical contribution is a recent development in English patent law that has come from the Technical Boards of Appeal of the EPO (specifically AgrEvo (T 939/92) and Johns Hopkins (T 1329/04)). It is currently an area of fast developing law. However, the Court of Appeal is clear that their decision on post-dated evidence does not affect the general rule that assessments of obviousness must be made as at the priority date of the patent.

Read the decision (PDF)

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