The "Plausibility" Requirement At The EPO

Decision T 488/16 of the Boards of Appeal of the EPO has been published setting out the reasoning for the revocation of European patent number EP1169038 protecting the anti-cancer drug dasatinib (Sprycel®).  The Decision represents an interesting development of the doctrine of "plausibility", particularly in relation to small molecule pharmaceuticals.

The patent owner had sought to defend the patent on the basis of just one claim directed to the single compound dasatinib.  The novelty of this compound was not in dispute, and the case hinged on the extent to which the patent owner was entitled to rely on the activity of the compound (as a PTK inhibitor) as a technical effect when seeking to establish an inventive step.