Enlarged Board of Appeal rules on double patenting

Managing IP is part of Legal Benchmarking Limited, 1-2 Paris Gardens, London, SE1 8ND

Copyright © Legal Benchmarking Limited and its affiliated companies 2026

Accessibility | Terms of Use | Privacy Policy | Modern Slavery Statement

Enlarged Board of Appeal rules on double patenting

Sponsored by

maiwald-logo-cropped.PNG
butterflies-1127666-1280-1.jpg

Annelie Wünsche and Stefanie Parchmann of Maiwald discuss double patenting before the EPO

On June 22 2021, the Enlarged Board of Appeal of the European Patent Office issued decision G 4/19 (Double patenting), in which it held that a European patent (EP) application can be refused if it claims the same subject matter as a granted European patent (i.e. not just a co-pending EP application) which has been granted to the same applicant and has the same effective date. 

The application can be refused irrespective of whether it (a) was filed on the same date as, or (b) is a parent application or a divisional application of, or (c) claims the same priority as the European patent already granted.

In other words: if an applicant already achieved grant of an EP patent on a certain subject matter, the Examining Division will deny grant to claims on the ‘same’ subject matter in later examination proceedings pertaining to an application having the same ‘effective date’ as the granted patent.

This even applies if the EP patent that was granted earlier is the priority application of the later-examined application. The advantage of a longer term of protection (due to the later filing date) that is thus lost for the applicant is no justification for allowing double patenting.

The Enlarged Board of Appeal relied on Article 125 EPC, which stipulates that “in the absence of procedural provisions in this Convention, the European Patent Office shall take into account the principles of procedural law generally recognised in the Contracting States”.

Two pieces of the puzzle, however, were deliberately not examined by the Enlarged Board of Appeal. First, even though the referring Board asked for clarification, the concept of ‘same subject matter’ was not addressed (does overlap also count?). Second, the question whether the rules on double patenting will also have to be applied in opposition proceedings remained unanswered.

But we notice that a distinction between ‘double protection’ (claims with overlapping scope) and ‘double patenting’ was made in the Reasons, and we are therefore quite confident that the prohibition of double patenting will remain a prohibition of double patenting in a narrow sense, limited to claims on exactly the ‘same’ invention. Overlapping claims should, therefore, remain admissible.

Thus, tailoring the claims of the later application to a merely overlapping claim scope might still provide the possibility to get the later application granted. It remains to be seen whether filing a request for revocation of the earlier patent will be allowed as a means to address a double patenting situation. 

We are also curious to see whether double patenting rules will now be applied more often in opposition proceedings; at present, applying them is within the discretion of an opposition division. 

 

Annelie Wünsche

Partner, Maiwald 

E: wuensche@maiwald.eu

 

Stefanie Parchmann

Partner, Maiwald 

E: parchmann@maiwald.eu

 

 

more from across site and SHARED ros bottom lb

More from across our site

A Tokyo District Court ruling concerning movie spoilers, and a second chance for VLSI against Intel were also among the top talking points
Practitioners believe new AI tools at the USPTO will not replace lawyers or disrupt revenue, but instead expose where a trademark attorney’s value lies
Leighton Cassidy Legal hopes to leverage its founder's international experience and provide clients with a rare chance to receive litigation and prosecution under one umbrella
UKIPO rejects trademark application for 'Cristiano Ronaldo Origins' following opposition by Beck Greener client in a rare case that considered actual use
Partners at both firms have voted in favour of the tie-up, which marks ‘the largest law firm merger in history’
Head of IP, Andrew Brennan, and new partner, France Delord, explain how tech provides an edge in the battle for global brand owners’ business
Anton Hopen, shareholder at Trenam Law, shares how counsel should construct Section 101 claims as early 2026 PTAB data shows reversals rising in technical cases
Law firms should consider how they can help clients, as report calls on EU to use IP-backed financing to increase bloc’s competitiveness and attractiveness for businesses
In the final part of a series on challenging patent invalidation decisions in China, lawyers at Spruson & Ferguson and Marshall Gerstein share how courts adjudicate appeals
Stijn Debaene and Carina Gommers want Brussels-based Cast Law to be the place 'everybody wants to work'
Gift this article