Osha Attorneys
Osha Attorneys
Osha Attorneys
Osha Attorneys
Attorney search
Search by

The collective expertise of our global team distinguishes OBWB in the field of Intellectual Property Law. We align our best resources to meet each client's specific needs and we treat each matter with the highest degree of attention and care.

Decision G4/19 On Double Patenting Before the European Patent Office

日本語    简体中文    繁體中文


In decision G4/19 issued on June 22, 2021, the Enlarged Board of Appeal (EBA) of the European Patent Office (EPO), which is the highest degree of jurisdiction of the EPO, clarified on what basis a European patent application can be rejected for reasons of “double patenting”, i.e., the prohibition of having two patents granted to the same applicant and on the same invention. 


Although the concept of double patenting is known and applied in several jurisdictions, this concept finds no explicit basis in the European Patent Convention (EPC), the law governing the European patent system. Consequently, in order to reject a European patent application due to double patenting, the EPO, before decision G4/19 was issued, generally relied on contextual case law such as the cases outlined in the obiter dictum of decisions G1/05 and G1/06. The EPO even denied the existence of any legal basis justifying the refusal of a divisional application relating to the same invention as the parent (Board of Appeal decision T587/98), which led to confusion and uncertainty on the matter.

In the present case, the EBA analyzed the question referred to by a Board of Appeal relating to a patent application from Société des Produits Nestlé, which claimed subject-matter identical to the subject-matter claimed in the patent granted for the patent application from which the application-in-suit claimed priority (T318/14). The EBA concluded that, although not explicitly mentioned in the EPC, the prohibition of double patenting is widely accepted as a part of “general principles procedural law generally recognised in the Contracting States” of the EPCthat may be applied even in the absence of explicit provisions of the EPC, as provided by Art. 125 EPC.

In order to reach this conclusion, the EBA dug into the preparatory works of the EPC and found out, inter alia, that “In connection with Article 125, it [is] a generally recognized principle that a person can be granted only one European patent for the same invention in respect of which there are several applications…”. Therefore, in decision G4/19, the EBA interpreted Art. 125 EPC as encompassing the principle of double patenting.

Moreover, the EBA held that the rejection for double patenting is applicable not only in case of an application claiming priority of an earlier application (case i), but also when two patent applications are filed on the same day (case ii), or when a divisional application is filed from a parent application (case iii).

The filing of a European application claiming the priority of an earlier European application is particularly important as it implies that an applicant cannot obtain a new European patent with the same set of claims as that of a European patent granted for an earlier European priority application. This possibility was sought by applicants with the aim of extending the period of protection provided by an identical (or nearly identical) claim to up to one year, corresponding to the maximum period available from the filing date of the priority application to the filing date of the subsequent application claiming priority thereto. This attempt of extending the period of protection by way of a priority claim is clearly ruled out by the decision G4/19 of the EBA.

Finally, the EBA confirmed that the prohibition of double-patenting only applies in the case that the application under examination and the patent already granted have common designated Contracting States, which, due to the automatic designation of all the Contracting States when paying the designation fee to the EPO without withdrawing any of them, is the standard case.

Unfortunately, in view of the case underlying the appeal which lead to decision G4/19, no guidance can be inferred as to the extent to which two inventions are considered as the same invention by the EPO. The standard for assessing the two inventions could be the same as that applied when assessing the validity of a priority claim, which, according to Art. 87 EPC, also requires the presence of the “same invention.” This standard, as established by decision G2/98, is rather strict. Should the standard used to assess double patenting be the same as that used in the assessment of validity of a priority claim, it could be relatively easy to sufficiently distinguish the invention claimed in a second application with respect to the invention claimed in a first application falling within one of cases i-iii identified above. However, it cannot be excluded that a different interpretation of “same invention” could be followed by a European Examiner when the question of double patenting is raised. For example, the Guidelines for Examination, C-IX, 1.6, state without authority that “the difference between the claimed subject-matter of [a divisional application and a parent application] must be clearly distinguishable.” In order to at least reduce the risk of an objection of double patenting and the consequent refusal of a second application to the same applicant, the second application should thus claim subject matter including at least one feature clearly distinct and conferring a scope of protection either overlapping with the scope of the first application only partially (as in T877/06) or, to completely eliminate such risk, not overlapping at all.

A further uncertainty relates to the concept of “same applicant.” Should the EPO follow a strict approach, as, for example, in T788/05 or J2/01, then the addition of an applicant would be sufficient to have distinct applicants. A broader approach, however, cannot be excluded either because this aspect has not been considered in detail by the EBA either.

In view of the above, there is an additional reason to draft European applications clearly disclosing an adequate number of embodiments not only as potential fallback positions for patentability purposes, but also for non-double patenting purposes.