3.1. Bindung an die Anträge – Verbot der "reformatio in peius"

In T 246/23 of 11 March 2026 the board rejected the objection under Art. 24(3) EPC and refused the opponent's request for cost apportionment.

During the oral proceedings in T 246/23 of 7 August 2025, when the debate on auxiliary request 5 was opened, the board in its original composition (the "original board") had informed the parties of its preliminary view that the request contravened the principle of no reformatio in peius. The patent proprietor (respondent) had then raised an objection of suspected partiality against all board members, arguing that an objection based on this principle could only be raised by another party, not by the board. It submitted that, since the board had raised the objection ex officio, it was "on the side" of the opponent (appellant) and thus suspected to be partial. The original board had found the objection admissible and the composition of the board was changed for the purposes of a decision on the objection under Art. 24(3) EPC (the board in its new composition in the following referred to as "the board").

The board noted that, on the substance of the objection, the respondent relied on two core arguments, neither of which was convincing: (1) that the specific nature of the prohibition of reformatio in peius prevented the board from raising it ex officio, and (2) that established case law supported this view.

On (1), the board stated that the prohibition of reformatio in peius is not so exceptional as to completely escape the board's powers under Art. 114 EPC. It noted that any objection raised by the board ex officio in an inter-partes procedure can be perceived as being in a certain contradiction with the board's obligation to remain neutral towards the parties. However, if the parties were free to raise the objection of suspicion of partiality in all cases where a board exercises its powers under Art. 114 EPC, such powers would be effectively eliminated. The board also rejected the argument that raising the prohibition ex officio contradicts the principle of party disposition. This principle concerned the substantive outcome of proceedings, i.e. the scope of the legal effects sought, and did not extend to the legal arguments raised by either the parties or the court for achieving the requested legal effects. In the present case, the opponent requested the revocation of the patent, and the original board's finding that auxiliary request 5 was not allowable, for whatever reason, was clearly within the scope of the appellant's appeal request for revocation.

On (2), the board pointed out that there was no settled case law forbidding the board from raising the objection ex officio. It added that this could not even be derived from cited decision T 1544/07. In its view, T 1544/07 only found that the deciding board had no obligation to raise the objection under the special circumstances of that case, where the opponent itself had explicitly waived the right to raise it. The decision did not state that a board is prevented from raising the objection ex officio as a question of principle. Rather, it appeared to suggest that a board may, but need not, raise it where the affected party renounces this defence. A far stricter position was taken in T 882/17, cited by the opponent, where the deciding board disagreed with T 1544/07 and unambiguously stated that the board not just may, but must take the prohibition into account, and also ex officio. This decision was followed by other decisions (T 1773/22, T 1472/21).

The board explained that, to decide the issue before it (i.e. the objection of suspected partiality) it was sufficient to establish that, contrary to the proprietor's argument, case law was far from settled. The mere existence of another line of case law, T 882/17, recognising the board's entitlement to raise the prohibition objection, was sufficient to establish that the original board could not be considered partial solely for raising the objection. According to the board, a board of appeal is always entitled and in fact obliged to examine the boundaries of its own powers to raise an ex officio objection. If necessary, it is also entitled to question findings of previous decisions on the same issue. The original board was under no obligation to seek the proprietor's permission or to maintain the objection only contingent on the opponent's intention to pursue it.

The board concluded that the objection under Art. 24(3) EPC was unsubstantiated. It also refused the opponent's request for cost apportionment, noting that it could not qualify the procedural conduct of the proprietor as an abuse of procedure.