Enlarged Board of Appeal rules on double patenting

Managing IP is part of Legal Benchmarking Limited, 4 Bouverie Street, London, EC4Y 8AX

Copyright © Legal Benchmarking Limited and its affiliated companies 2025

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

Managing IP considers some of the key themes from the 2025 Annual Meeting and offers some tips for London 2026
A comparison of the 2024 and 2025 editions of the Managing IP EMEA Awards reveals the firms and companies that have been dominating Europe’s IP market year after year
Tuesday's coverage includes BD tips for aspiring partners, and a foray into the world of SEPs
Exclusive data reveals law firms are failing to go above and beyond for their corporate clients, with in-house counsel saying advisers should consider more transparent billing processes
Arty Rajendra and Gary Moss discuss why ‘thorough and intense’ preparation, plus the odd glass of wine, led to a record FRAND victory for their client
Monday’s coverage includes news of a potentially 'game-changing' trademark development in China and how practitioners are using AI
Managing IP gives a taster of the numbers behind this year’s IP STARS trademark rankings, and looks back at our 2025 award winners
Updates from IP offices, the shifting requirements of in-house counsel, and news of London 2026 were among major talking points on Sunday
Etienne Sanz de Acedo discusses the association’s three-year plan, what he is looking forward to in San Diego, and why London came calling for 2026
Professionals from three organisations reveal what led them to sponsor Brand Action and why doing so can build camaraderie
Gift this article