• Admissibility of Post-Dated Evidence

    [2012] EWHC 1848 (Pat)

    Generics [UK] Limited (trading as Mylan) vs Yeda Research and Development Co. Ltd and Teva Pharmaceutical Industries Limited

    In his decision of 11th July 2012, Mr Justice Arnold (Patents Court) has provided some clarification with respect to the admissibility of post-dated evidence.

    One of the many issues addressed was the obviousness of the patent for lack of technical contribution, which raised the following questions:

    1. If the patent when read with the skilled person's common general knowledge did not "disclose enough to make the invention plausible", i.e. plausible that the invention solved the technical problem, then is it permissible for the patentee to rely upon evidence which post-dated the patent to demonstrate the technical effect?
    2. If a patent does disclose enough to make the invention plausible at the priority or filing date, can an opposing party came along 20 years later and say that, in the light of subsequently acquired knowledge, in fact the invention does not have the technical benefit that it appeared to have?

    "Just as a patent which does not make the invention plausible cannot be supported by post-dated evidence, then a patent which does make the invention plausible cannot be shown to be obvious by post-dated evidence. Either way, the fundamental principle is that whether a claimed invention is obvious or not should be judged as at the priority or application date."

    "The position is different in the case of evidence which is extrinsic to, but contemporaneous with, the Patent."

    "Post-dated evidence may be relied on to confirm that the disclosure in the patent either does or does not make it plausible that the invention solves the technical problem. Post-dated evidence may not be relied upon either to establish a technical effect which is not made plausible by the specification in order to rebut an allegation of obviousness or to contradict a technical effect which is made plausible by the specification in order to found an allegation of obviousness. In my view it would be bizarre if, as counsel for Mylan submitted, a patent which at the time it was applied for disclosed what everyone thought was a good invention could be revoked 20 years later because subsequent advances in science had revealed that in fact the invention did not solve the technical problem."

    "If the specification does make it plausible that the invention solves the technical problem, I do not consider that it is open to an applicant for revocation to rely upon post-dated evidence as casting doubt on this so as to place an evidential burden on the patentee to demonstrate affirmatively that the invention does solve the technical problem."