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EPO: Double Patenting; G 4/19

On 22 June 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 application can be refused if it claims the same subject-matter as a 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 – and this is a big snatch to be taken into account by any applicant of an application claiming priority from an EP application in the future – if the 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 in this scenario (scenario (c)).

The Enlarged Board of Appeal heavily relied on the Travaux Preparatoires for Art. 125 EPC to reach this conclusion.

Article 125 EPC 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.

The Enlarged Board of Appeal held that the term “procedural provisions” in Article 125 EPC extends to provisions requiring a substantive examination (another example being Art. 123(2) EPC, added matter), and that the prohibition on double patenting constitutes a principle 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. Time will tell.

Here´s the link to the decision:$FILE/G_4_19_decision_of_the_Enlarged_Board_of_Appeal_of_22_June_2021_en.pdf

Our blog contributions shall provide an overview with regard to legal topics, legislation and case law and are supposed to provide some general information rather than constituting any specific advice. Please do not hesitate to contact Maiwald and in particular the authors of the particular contributions if have any questions on the addressed topics or on other legal issues.

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Dr. Stefanie Parchmann


German Patent Attorney

European Patent Attorney