Generics [UK] Ltd (t/a Mylan) v Yeda Research and Development Co Ltd & Anor

A patent monopoly must correspond to the technical contribution made across substantially the whole scope of the claim. A technical effect must be plausible from the specification before it can support inventive step. Later evidence may support that effect and may also prove that it does not exist. Negating the asserted effect does not automatically establish obviousness, because another, less ambitious contribution may remain.

A patent claim may have a permissible fuzzy boundary where the skilled person understands the criterion to apply. It is insufficient for ambiguity only where the correct test for infringement is unclear. An applicant seeking a declaration of non-infringement bears the burden of proving that its product falls outside the claim.

Mylan sought revocation of a patent concerning lower-molecular-weight copolymer-1 compositions used in treating relapsing-remitting multiple sclerosis, together with a declaration that its proposed competing product would not infringe. Arnold J rejected both claims in [2012] EWHC 1848 (Pat).

Mylan appealed on four principal grounds: obviousness over the Johnson 1994 publication; obviousness because the patent lacked the asserted technical contribution; non-infringement on the proper construction of the claimed amino-acid ratio; and ambiguity-type insufficiency if its proposed construction was rejected. The appeal therefore concerned inventive step, the admissibility of later evidence concerning technical effect, patent construction, infringement and sufficiency.

1. Appeal dismissed. Floyd LJ, with whom Kitchin and Moses LJJ agreed, held that Arnold J had correctly dismissed the revocation action and refused the declaration of non-infringement.
2. The judge was entitled to find that the invention was not obvious over Johnson 1994. The publication left the skilled team uncertain whether the successful clinical trial had used 7 kDa material or the earlier 14–23 kDa material. The skilled team would not necessarily have pursued both forms while clarification was expected. The earlier material also had the better-established safety and efficacy data, while reducing molecular weight moved the product further from the myelin basic protein it was designed to mimic.
3. The scope of a patent monopoly must be justified by its technical contribution to the art. A claimed technical effect must extend to substantially everything within the claim. An arbitrary selection lacking a useful technical effect is likely to be obvious. The specification must make the effect plausible, although later evidence may support an effect which has crossed that threshold.
4. The judge erred in holding that later evidence could not contradict a technical effect made plausible by the specification. Evidence concerning the invention's true technical effect is relevant to identifying the contribution against which inventive step is assessed under article 56 of the European Patent Convention. If the asserted effect is disproved, obviousness does not follow automatically. The patentee may rely on a less ambitious contribution, and the challenger must still prove obviousness by reference to the skilled team's knowledge and conduct at the priority date. On the evidence, however, Mylan failed to establish that lowering molecular weight produced no clinically meaningful difference.
5. The expression “approximately 6:2:5:1” allowed for variability arising from amino-acid analysis and copolymer-1 synthesis. A sample fell outside the claim only if its departure from that ratio exceeded such variability. The judge's reliance on an illustration suggesting that a 29.6% variation in tyrosine was necessarily tolerable was incorrect, but Mylan had not proved that this variation exceeded the relevant analytical and manufacturing variability. It therefore failed to establish non-infringement.
6. The claim had a fuzzy boundary rather than true ambiguity. The skilled person knew the criterion to apply, even though evidence was needed to quantify its boundary. The insufficiency challenge accordingly failed.

1. Court of Appeal (Civil Division): The appeal was dismissed unanimously. The refusal of revocation and of a declaration of non-infringement was upheld: [2013] EWCA Civ 925 .
2. High Court, Patents Court: Arnold J dismissed Mylan's revocation action and refused its declaration of non-infringement: [2012] EWHC 1848 (Pat) .