On Wednesday, the Court of Appeal handed down a decision upholding Astellas’ enzalutamide patent. Appeals on the question of obviousness are notoriously difficult to overturn, given that so many of the findings underpinning such a decision are factual. In the words of Zacoroli LJ: “a conclusion on obviousness is a highly fact-dependent evaluative decision where the judge who has been immersed in the detail of the case has a significant advantage over an appellate court. That is particularly so in a specialist area in which the judge is well-versed, and where the judge has heard the cross-examination of the technical experts.”
The full decision can be found here.

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