01/03/2022
Article 4 of the Paris Convention of 1883 enshrined the principle of an applicant when filing a patent application to be able to claim priority from a previous patent application for the same invention filed up to 12 months beforehand. A valid priority claim can serve several useful purposes, including establishing the date for determining what published documents or other “prior art” can be cited against the subsequent application for assessing patentability. Recently developments at the European Patent Office (EPO) reveal that there are still uncertainties and differences in various jurisdictions on what constitutes a valid claim to priority.
An EPO Board of Appeal confirmed two years ago in decision T844/18 (“CRISPR-Cas/Broad Institute”) that, according to EPO practice, for a priority claim to be valid the applicant(s) for the subsequent application must be the same as the applicant(s), or their successor(s) in title, of the previous patent application. In T844/18, a US priority application named more applicants (inventors) than the subsequent PCT application from which the European patent was derived. The Board of Appeal held that since the omitted applicant had not transferred his rights to the applicants of the PCT application, the priority claim was invalid. Unfortunately for the patentee, this brought additional prior art into the frame and the patent was deemed invalid.
Now, an EPO Board of Appeal in cases T1513/17 and T2719/19 (both “Prolongation of survival of an allograft/Alexion”) has referred questions concerning priority entitlement for joint applicants to the Enlarged Board of Appeal, the EPO’s highest authority on questions of law. In the pending referrals, consolidated as G1/22 and G2/22, the following questions have been raised:
“I. Does the EPC [European Patent Convention] confer jurisdiction on the EPO to determine whether a party validly claims to be a successor in title as referred to in Article 87(1)(b) EPC?
II. If question I is answered in the affirmative:
Can a party B validly rely on the priority right claimed in a PCT-application for the purpose of claiming priority rights under Article 87(1) EPC in the case where:
1. a PCT-application designates party A as applicant for the US only and party B as applicant for other designated States including regional European patent protection;
2. the PCT-application claims priority from an earlier patent application that designates party A as the applicant;
3. the priority claimed in the PCT-application is in compliance with Article 4 of the Paris Convention?”
It is widely expected that Question I will be answered “Yes”. Question II relates to the so-called “joint-applicants approach” which holds that naming one or more further applicants in a subsequent application does not negate the priority right if the applicant(s) of the earlier application are also named as a joint applicant (see Guidelines for Examination at the EPO, section A-III, 6.1). However, the further uncertainty in cases T1513/17 and T2719/19 concerns the following specific scenario. The previous application is a US application naming the inventors Rother, Wang and Zhong as applicants. Those inventors are then named as applicants only for the US designation for a subsequent Patent Cooperation Treaty (PCT) International application, whereas a company (Alexion Pharmaceuticals) is named as applicant for other designations including the European application. Will the PCT application be considered to have a unitary character, allowing the joint-applicants approach be followed in this scenario?
We look forward to the Enlarged Board of Appeal’s ruling.
This article is for general information only. Its content is not a statement of the law on any subject and does not constitute advice. Please contact Reddie & Grose LLP for advice before taking any action in reliance on it.
