EPO Enlarged Board of Appeal decision G4/19 – a European patent application can be refused by reason of the prohibition on double patenting

The European Patent Office today confirmed in Decision G4/19 of the Enlarged board of Appeal that a European patent application can be refused for ‘double patenting’.  Such a refusal can be made even absent the European Patent Convention having an explicit double patenting provision.

The claiming of the same subject matter in two applications having the same filing or priority date to the same Applicant is referred to as double patenting.  The European Patent Convention does not contain an explicit prohibition against this practice. However, previous decisions against double patenting have relied upon a reference to general principles of patent law in EPC Contracting States embodied in Article 125 EPC.  For example, Section 18(5) of the UK Patents Act provides such an explicit double patenting provision.  It was argued that the double patenting provision embodied in Article 125 EPC only prevented double patenting in the case of applications filed on the same day or between a divisional application and its parent.

The Enlarged Board of Appeal confirmed that Article 125 EPC compelled the EPO to refuse applications for double patenting by taking into account national law of Contracting States.  Furthermore, the Enlarged Board found that double patenting is also prohibited in the case of internal priority i.e. where two applications benefit from the same priority and claim the same subject matter.

It is worth pointing out that the EPO only construes the probation on double patenting narrowly in order to prevent two patents claiming the same identical subject matter.  Therefore, where differences exist between the claims, the double patenting prohibition should not apply.

This article was prepared by HGF Partner Chris Benson. If you would like further advice on this or any other matter, please contact Chris. Alternatively, you can contact your usual HGF representative or visit our Contact page to get in touch with your nearest HGF office.