Decision G 4/19 of the Enlarged Board of Appeal on the Issue of Double Patenting
On June 22, 2021, the Enlarged Board of Appeal (EBA) of the European Patent Office (EPO) issued decision G 4/19 on the topic of double patenting. The EBA held that a European patent application can be refused if it claims the same subject matter as a European patent which has been granted to the same applicant and has the same effective date. Essentially, the EBA stated that the later application can be refused under all possible constellations of the earlier patent and the later application having the same effective date.
The principle of the prohibition on double patenting excludes two patents being granted to the same applicant for one invention. The referring examining division applied this principle and refused a European patent application under Articles 97(2) and 125 EPC on the ground that the applicant already had a patent for the same invention. The applicant appealed and the Technical Board of Appeal referred three questions on the prohibition on double patenting to the EBA (T 0318/14). The referring board doubted there was a legal basis for the prohibition in the EPC. In particular, the referring board did not consider Article 125 EPC suitable for that purpose.
1. The following questions were referred to the EBA in case T 0318/14: Can a European patent application be refused under Article 97(2) EPC if it claims the same subject matter as a European patent that was granted to the same applicant and does not form part of the state of the art pursuant to Article 54(2) and (3) EPC?
2.1 If the answer to the first question is yes, what are the conditions for such a refusal, and are different conditions to be applied depending on whether the European patent application under examination was filed.
a) on the same date as: or
b) as a European divisional application (Article 76(1) EPC) in respect of or
c) claiming the priority (Article 88 EPC) in respect of a European patent application on the basis of which a European patent was granted to the same applicant?
2.2 In particular, in the last of these cases, does an applicant have a legitimate interest in the grant of a patent on the (subsequent) European patent application in view of the fact that the filing date and not the priority date is the relevant date for calculating the term of the European patent under Article 63(1) EPC?
The EBA answered the referred questions as follows:
1. A European patent application can be refused under Articles 97(2) and 125 EPC if it claims the same subject matter as a European patent which has been granted to the same applicant and does not form part of the state-of-the- art pursuant to Article 54(2) and (3) EPC.
2.1 The application can be refused on that legal basis, irrespective of whether it:
a) was filed on the same date as, or
b) is an earlier application or a divisional application (Article 76(1) EPC) in respect of, or
c) claims the same priority (Article 88 EPC) as the European patent application leading to the European patent already granted.
2.2 In view of the answer to Question 2.1; a separate answer is not required.
This means that, if an applicant already has an EP patent granted 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. It should be noted that the prohibition only extends to the examination proceedings, not to opposition proceedings.
The double patenting prohibition even applies if the patent, which was granted earlier, is the priority application of the later-examined application (Answer 2.1 (c)). Thus, the longer term of protection due to the later filing date of the younger application was considered as not representing a legitimate interest for justifying double patenting.
Reasoning of the EBA
For their reasoning, the EBA relied on Art. 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 recognized in the Contracting States”. The EBA held that the term “procedural provisions” in Article 125 EPC may extend to provisions requiring a substantive examination of the subject matter claimed. It stated that the prohibition on double patenting constitutes a principle of procedural law within the meaning of Article 125 EPC and is generally recognized in the Contracting States.
For determining what the generally recognized principles are in the context of the referral, the EBA interpreted Article 125 EPC in line with the principles set out in Articles 31 and 32 of the Vienna Convention on the Law of Treaties. Notably, the EBA further considered the preparatory documents for the drafting of the EPC (Travaux Préparatoires) for deriving whether the prohibition on double patenting was a “principle generally recognized in the contracting states”, and thus fell under Article 125 EPC.
In particular, in the Minutes of the Proceedings of the Main Committee I regarding Article 125, it was found that a majority of member states supported a prohibition of double patenting. Only Norway objected explicitly. It is an interesting thought that committee decisions that were once not directly incorporated into the EPC later may lead to severe implications regarding the construction of the EPC.
The EBA further held that the prohibition on double patenting is not limited to applications directed to the same subject matter that were filed on the same day. It also extends to parent and divisional applications, and to applications claiming the same priority. The EBA also confirmed that the prohibition only applies where the application under examination and the patent already granted have common designated Contracting States.
Repercussions of G 4/19
Decision G 4/19 follows the established practice (Ne bis in idem) outlined by decisions G 1/05 and G 1/06, where it was stated that an applicant does not have a legitimate interest in the grant of a second patent to the same subject‑matter, even if there is no explicit prohibition of double patenting in the EPC.
On the other hand, decision G4/19 contradicts the opinion of the Board of Appeal in T 1423/07, where the board found that Article 125 EPC did not provide proper legal basis for the prohibition. However, the Board in T 1423/07 decided that double patenting was not an issue in this case because the granted patent and the application claiming priority of that patent had different applicants. Specifically, the priority claiming application had been assigned to a new applicant after its refusal, whereas the rights of the priority-establishing patent still belonged to the original applicant.
Several amicus curiae briefs had been filed before the decision was made and, after the decision was issued, there is concern regarding the possible loss of valuable assets. The reason is that many applicants see they are losing the possibility of an extended term of protection provided by a later filed application. In the future, it has to be considered by applicants to avoid the earlier application maturing into a patent with the broadest possible scope in order to benefit from the longer term of a later application with a broader scope claiming the priority of the earlier application. Also national patent or utility model applications may advantageously be used as priority applications, even if those might be superseded by the EP patent in several jurisdictions.
Furthermore, the referring decision and some of the amicus curiae briefs asked the EBA to clarify the meaning of the terms “same invention/same-subject matter” and “same applicant”. These questions, however, were not addressed by the EBA. Hence, it remains to be seen whether assigning the priority application and the later application to different applicants before grant will be a possibility to circumnavigate the implications of G 4/19.
It also remains to be seen in the future how the “same-subject matter” will be interpreted. G 4/19 does not give any guidance or definition of how narrow or broad this term will have to be interpreted. It seems, however, that the interpretation will be rather narrow, so that the prohibition only applies to identical subject matter. If the claims differ, it should not be a case of double patenting. Further, as mentioned above, it was not decided in G4/19 whether the above framework also has to be applied to opposition proceedings.
As an aside, it seems that by applying a similar reasoning based on Art. 125 EPC, other issues that do not have an explicit regulation in the EPC, e.g. the requirements for a valid transfer of the priority right, may be reassessed in the future.