The EPO has revoked one of the Broad Institute’s core patents relating to the CRISPR gene editing technology.

The patent claimed priority from US applications which were filed by a number of joint applicants. The revoked patent omitted one of these applicants and the Broad Institute did not show that any right of priority had been assigned. The Broad Institute argued that since the omitted applicant was not entitled to the inventions in the patent, it should not need to demonstrate that an assignment of the priority right took place. However, the EPO held that the claim to priority was invalid which brought intervening prior art into play.

The decision confirms that the right to priority is a stand-alone right which depends on the named applicants, and not on entitlement to the underlying invention.

The Broad Institute has appealed the decision and released a press release alleging that the EPO’s decision is not in line with a proper interpretation of the Paris Convention (which gives rise to the priority right).

Whichever way the appeal goes, this case highlights the importance of assigning any priority rights before a later application is filed.