In T 1178/04 (OJ 2008, 80) the board held that where the issue was a person's right to be a party, the principle of no reformatio in peius was of no application, bearing in mind the fact that the principle of no reformatio in peius was taken mainly from the well-established principle in German law ("Verschlechterungsverbot"). This principle has no application in those cases where (a) there exist procedural preconditions for making relevant requests to the court ("Verfahrensvoraussetzungen") and (b) these preconditions are of a kind that cannot be waived or dispensed with ("unverzichtbare Verfahrensvoraussetzungen"), such that the court must itself be satisfied that they have been fulfilled. According to the board, in the context of patent proceedings such as these, preconditions of this kind included the admissibility of the opposition itself and the capacity of a person to be a party to the proceedings in the first place.

Referring to T 1178/04, the board in T 384/08 found that the admissibility of the opposition is an indispensable procedural requirement for the substantive examination of the opposition submissions at every stage of the proceedings. The board therefore had to examine the question of the transfer of status of the opponent ex officio before dealing with the substance of the case.