Zusammenfassung von Article 099 EPC für die Entscheidung T1403/24 vom 08.09.2025

In T 1403/24 the appellant (patent proprietor) contested the admissibility of the opposition filed by opponent 2. It argued that opponent 2 was acting on behalf of opponent 1 or opponent 3. In the appellant’s view, this followed from the citation of document D24 in the notice of opposition by opponent 2, because D24 concerned the non-public infringement complaint by the patent proprietor against opponent 1 and opponent 3 in Germany. Moreover, opponent 2 had previously represented a member of the same company group to which opponent 1 belonged in the opposition against the parent patent. Furthermore, the notices of opposition filed on the same day by opponent 2 and opponent 3 included large sections of identical language. As explained in T 9/00, it would be an abuse of procedure for one opponent to file two oppositions. Therefore, according to the appellant, the filing of the opposition by opponent 2 on behalf of opponent 1 or opponent 3 represented an attempt to circumvent the law, which was in view of the considerations in G 3/97 and G 4/97 not admissible. The board observed that in contrast to the situation in T 9/00, opponent 2 was a distinct legal person from opponent 1 and opponent 3. According to decisions G 3/97 and G 4/97, an opposition filed on behalf of a third party was inadmissible if the involvement of the opponent was to be regarded as circumventing the law by abuse of process, in particular if the opponent was acting on behalf of the patent proprietor or on behalf of a client without possessing the relevant qualifications required by Art. 134 EPC. The decisions G 3/97 and G 4/97 explicitly concluded that a circumvention of the law by abuse of process did not arise purely because a professional representative was acting in its own name on behalf of a client and that the burden of proof regarding the circumvention of the law by abuse of process was to be borne by the party alleging that the opposition was inadmissible. The board held that, given the shared interest among opponents in revoking the patent, it was not uncommon for them to exchange documents and coordinate their submissions during opposition proceedings. Therefore, the citation of document D24 by opponent 2, and the presence of similar or identical passages in the notices of opposition filed by opponents 2 and 3, did not establish that opponent 2 acted on behalf of opponent 1 or opponent 3. The appellant had thus not provided convincing evidence that the opposition filed in the name of opponent 2 was filed on behalf of opponent 1 or opponent 3 to circumvent the law by abuse of process. Accordingly, the board confirmed the admissibility of the opposition filed by opponent 2.