UK Supreme Court judgement in long-running dispute between Eli Lilly and Actavis on the combination therapy pemetrexed + vitamin B12 results in significant outcomes for patent infringement in the UK

In a judgement issued on 12 July, the UK Supreme Court made some significant changes in the law of UK patent infringement which could have far reaching consequences, especially in the pharmaceutical sector. In particular, they addressed the issue of infringement by equivalents not otherwise falling within the literal claim scope and also the extent to which the patent prosecution history can be used as a guide to claim interpretation.

The judgement concerned the long-running dispute between Eli Lilly and Actavis on the combination therapy pemetrexed + vitamin B12 and is surely a victory for pharmaceutical originators who may now have more breathing space in catching out potential infringers with even a rather narrow claim. Briefly, Eli Lilly were granted a second medical use claim to pemetrexed disodium in combination with vitamin B12, and Actavis’ products containing either the pemetrexed diacid or different pemetrexed salts were held to directly infringe Eli Lilly’s patent. This is a significant departure from current practice with respect to the interpretation of pharmaceutical patent claims, which are interpreted fairly literally based on the structure of the compound. The decision therefore has quite severe freedom-to-operate consequences for pharmaceutical generic companies, who may now consider revisiting their position on key infringement issues.

Beyond the pharmaceutical industry, this decision has implications for infringement and patent prosecution strategy for all fields of technology. The test for infringement of a claim by a product or process not exactly aligning with the claim scope has been altered and applies equally to all technologies, not just to pharmaceutical patents. Furthermore, the decision considers the circumstances under which the prosecution history (file wrapper) may be consulted in determining the scope of a patent claim in an infringement action.

If you would like us to review previous advice that you have received on an infringement issue to see if this may be affected by the latest decision, please contact us.