e) Priority 

In G 1/22 and G 2/22 (OJ 2024, A50), the Enlarged Board concluded that there is a rebuttable presumption under the autonomous law of the EPC that the applicant claiming priority in accordance with Art. 88(1) EPC and the corresponding Implementing Regulations is entitled to claim priority. This presumption is justified in view of the purpose of the priority rights, the lack of formal requirements for the transfer of priority rights and the presumed common interest of the priority applicant and the subsequent applicant (G 1/22 and G 2/22, points 105, 112 of the Reasons and point I of the Order). The presumption of priority entitlement and its rebuttal are, like the priority entitlement in general, subject to the autonomous law of the EPC only. It cannot be excluded, however, that in the context of the rebuttal of the presumption national laws need to be considered as well.

The rebuttable presumption involves the reversal of the burden of proof, i.e. the party challenging the subsequent applicant's entitlement to priority has to prove that this entitlement is missing. If there is a strong presumption, the hurdle for rebutting it is higher than in the case of a weak presumption (G 1/22 and G 2/22, point 109 of the Reasons, citing T 63/06).

The presumption that the subsequent applicant is entitled to the priority right is a strong presumption under normal circumstances since the other priority requirements (which establish the basis for the presumption of priority entitlement) can usually only be fulfilled with the consent and even cooperation of the priority applicant (G 1/22 and G 2/22, point 110 of the Reasons). The party challenging the entitlement can thus not just raise speculative doubts but must demonstrate that specific facts support serious doubts about the subsequent applicant's entitlement to priority.

See chapter II.D.2.4.1 ”Introduction” on Priority.