The Enlarged Board of Appeal of the European Patent Office (EPO) has issued its decision in consolidated cases G 1/22 and G 2/22.

The Enlarged Board of Appeal orders as follows:

• The European Patent Office is competent to assess whether a party is entitled to claim priority under Article 87(1) EPC.
  There is a rebuttable presumption under the autonomous law of the EPC that the applicant claiming priority in accordance with Article 88(1) EPC and the corresponding Implementing Regulations is entitled to claim priority.
• The rebuttable presumption also applies in situations where the European patent application derives from a PCT application and/or where the priority applicant(s) are not identical to the subsequent applicant(s).

In a situation where a PCT application is jointly filed by parties A and B, (i) designating party A for one or more designated States and party B for one or more other designated States, and (ii) claiming priority from an earlier patent application designating party A as the applicant, the joint filing implies an agreement between parties A and B allowing party B to rely on the priority, unless there are substantial factual indications to the contrary.

The referral by Technical Board of Appeal 3.3.04 in consolidated cases T 1513/17 and T 2719/19 (OJ EPO 2022, A92) raised two issues:

• firstly, it questioned whether the EPO has the authority to assess a party’s entitlement to claim priority;
• secondly, it addressed a scenario where inventors file a US patent application, which is then used as a priority application for a later PCT application in which the inventors are named as applicants for the US only, whereas for European patent protection, legal persons other than the inventors are named. In such a situation, the question arises whether the co-applicant of a PCT application who is different from the inventors named in the US priority application can validly rely on the priority right under Article 87(1) EPC.

In both cases underlying the referral, the Opposition Division and Examining Division respectively found that not all inventors who were named as applicants in the US patent application had assigned the priority right to the applicants of the respective European patent applications before filing of the PCT application. As a result, they deemed the priority claim invalid.

As per the above-mentioned order, the Board concluded that the European Patent Office (EPO) is authorized to evaluate priority entitlement and that there is a rebuttable presumption that an applicant who claims priority in compliance with the formal requirements under the European Patent Convention (EPC) is entitled to do so.

These are big decisions with effect in opposition practice: the hurdle to deny the right to priority is now higher for opponents.