Under Art. 106(2) EPC (formerly Art. 106(3) EPC 1973) a decision which does not terminate proceedings as regards one of the parties (interlocutory decision) can only be appealed together with the final decision, unless the decision allows a separate appeal. Separate appeal is possible against interlocutory decisions regarding admissibility of the opposition (see e.g. T 10/82, OJ 1983, 407) or maintenance of a patent in amended form (see e.g. T 247/85 and T 89/90, OJ 1992, 456).
In T 857/06, the opposition division had attempted to incorporate the content of its first (non-appealable) interlocutory decision into its second (appealable) interlocutory decision. No final decision had yet been taken and in its absence it could be argued that only the second interlocutory decision could be appealed and not the first. The board found that this would lead to a nonsensical procedural situation, where the board, while prevented from dealing with the appellant's main request, had to decide on lower-ranking requests. Art. 106(2) EPC had therefore to be construed in a purposive manner in this case, where the second interlocutory decision did not leave any substantive issues outstanding and was intended to form the complete basis for the maintenance of the patent in amended form. The first interlocutory decision had to be appealable together with the second (citing T 762/90 of 23 January 1991).