Some thoughts on EPO`s Enlarged Board of Appeal recent decision G4/19 referring to double patenting

According to the decision G4/19 dated June 22, 2021 by the Enlarged Board of Appeal, a European patent application can be refused under Articles 97(2) and 125 EPC if it claims the same subject-matter as a European patent that has been granted to the same Applicant and does not form part of the state of the art pursuant to Articles 54(2) and (3) EPC.

Further, it was decided that the application can be refused on this legal basis, irrespective of whether it
a) was filed on the same date as, or
b) is an earlier application or a divisional application (Art. 76(1) EPC) in respect of, or
c) claims the same priority (Art. 88 EPC) as
the European patent application leading to the European patent already granted.

The EPC does not deal explicitly with the case of co-pending European applications having the same effective date and filed by the same Applicant. However, it is an accepted principle in most patent systems that two patents cannot be granted on the same application for one invention. For example, Section 18(5) of the UK Patent Act provides an explicit double patenting provision as well as the well-established law of “Doppelschutzverbot” (prohibition on double patenting) in Germany. Thus, relying on Article 125 EPC the Enlarged Board of Appeal concluded that the prohibition on double patenting constitutes a principle of procedural law generally recognized in the contracting states.

It has been defined in the underlying decision T0318/14 that in the broadest sense the term “double patenting” means the simultaneous grant of two or more patents for the same invention having effect in the same territory. The recent decision G 4/19 suggests that the Enlarged Board of Appeal interprets the term “double patenting” in a rather narrow sense in order to prevent there are might be two patents from the same applicant claiming the same identical subject-matter. The Board seems to make a difference between “double protection” relating to claims with overlapping scope and “double patenting”. Thus, at present we expect that overlapping claims should remain admissible.

If two applications claiming the same identical subject-matter are desired for whatever reason, one can think of assigning one of the applications to another applicant or in an alternative one application could be filed at national patent offices.

However, as the term “same invention” has not been defined precisely by the Board, we assume, there will be more decisions necessary in the future to clarify this issue. In fact, the Board itself explained that the term “double patenting” itself may not be completely clear even if isolated from the specific situations addressed in the referral which is the basic for the decision and the relatively small body of existing Board of Appeal case law.

For example, it will have to be clarified if inadmissible double patenting affects opposition proceedings, and if yes, which influence an inadmissible double patenting will have on opposition proceedings.

The complete decision can be retrieved from:


Dr. Christian Heubeck, Dipl. -Chem., Dr. rer. nat., Patent Attorney, Partner Weickmann & Weickmann, Patent- und Rechtsanwälte PartmbB, Munich
Tel.: +49 (89) 455630 | E-Mail: cheubeck@weickmann.de