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Possible Referral to the Enlarged Board of Appeal on the Applicability of the “Joint Applicants Approach” (T 1513/17)

Whether a Euro-PCT application validly claims the priority of an earlier application is crucial to many proceedings before the EPO. In particular, doubts on a valid priority claim may arise if the priority application is filed by a party (A) (such as a US provisional application filed in the name of the inventor(s)) and the subsequent PCT application is filed in the sole name of another party (B) at least for some PCT countries (such as a legal person as applicant for EP), while (A) is listed as applicant for other, different countries in the PCT request, without the priority right being explicitly transferred from (A) to (B) before the time of filing of the PCT application for the countries in question (see e.g. T 577/11, T 1201/14).

If the priority claim is attacked, Patentees often argue for a valid transfer of the priority by the so-called “Joint Applicants Approach”, which is essentially based on the application of Art. 11(3) PCT in conjunction with Art. 118, 153(2) EPC. Accordingly, a PCT application request would have to be considered as a “unit” for which the priority would ─ due to the identity of applicant (A) for at least one country in the PCT request –“automatically” be validly transferred and claimed also in the remaining PCT member states such as the EPO for which (A) was not named as the applicant, but instead (B).

Whether this constellation is able to cure the lack of a formal transfer of the priority rights before the filing of the PCT application from (A) to (B) has not yet been finally answered by the Boards of Appeal with reference to the respective surrounding circumstances of the underlying cases (T 844/18, T 2431/17, T 407/15, T 205/14, T 1201/14). However, the Opposition and Examining Divisions of the EPO have recently given divergent answers to this question often acknowledging the validity of the priority claim.

In the preceding opposition proceedings of the present appeal T 1513/17, the applicability of the “Joint Applicants Approach” was not discussed, but European patent EP 1 755 674 B1 as granted was revoked in the light of two documents published in the priority period, which were considered to anticipate the claimed subject matter. On appeal, the Patentee relied on the “Joint Applicants Approach” for its priority claim.

The Board in case of T 1513/17 now appears to be of the view that the “Joint Applicants Approach” is decisive for the present case. Further, the Board in its Communication pursuant to Art. 15(1) RPBA dated February 2, 2021 indicated that the “Joint Applicants Approach” may be a point of law of fundamental importance and that at the oral proceedings it will be discussed whether a referral on this issue to the Enlarged Board of Appeal is appropriate. During the oral proceedings, it was suggested by the parties to additionally clarify related issues which had been addressed but not been decided in previous decisions of the Boards of Appeal (see e.g. T 844/18).

The Board 3.3.04 did not announce a decision on a possible referral to the Enlarged Board of Appeal at the end of the oral hearing but continued the proceedings in writing. However, it appears likely that the Board will refer questions related to the “Joint Applicants Approach” to the Enlarged Board of Appeal for further clarification of this point of law.

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Dr. Matthias Hoffmann


German Patent Attorney

M.Sc. Pharmaceutical Sciences