a) General 

Under Art. 108, sentence 3, EPC, the appeal has to be substantiated in line with the Implementing Regulations (R. 99(2) EPC). As per Art. 12(3) RPBA 2020, the statement of grounds of appeal and the reply have to contain a party's complete appeal case (see Art. 12(2) RPBA 2007).

Whether a statement of grounds meets the requirements of Art. 108 EPC can only be decided on a case-by-case basis (T 162/97, T 165/00, T 1435/11).

The board in T 1435/11 added that it was the boards' settled case law that the grounds for appeal had to set out an appellant's case – meaning not just its arguments but its requests too – in a way that was coherent, clear and sufficiently substantiated (see T 760/08, T 446/00). Indeed, the purpose of the statement of grounds, together with the notice of appeal, was to define the scope of the appeal. This definition was at the sole discretion of the appellant (see T 2532/11).

In T 23/10 the board stated that, whether or not sufficient grounds relating to the requests submitted, was immaterial for the purposes of the admissibility of the appeal, because an appeal can only be assessed as a whole. In other words, if the admissibility requirements of Art. 108, third sentence, EPC are fulfilled in respect of at least one request, let alone of several requests, the appeal as a whole will be admissible (T 509/07, T 1763/06). The fact that the appellant, in the course of appeal proceedings, withdrew the main and auxiliary request and thereby abandoned its refutation of the reasoning of the impugned decision under Art. 100(c) EPC, had no bearing on the assessment of the admissibility of the appeal as filed. The admissibility requirements of Art. 108, third sentence, EPC concerning the appeal filed by the patentee were met within the time limit for filing the statement of grounds of appeal at least as far as the main request and auxiliary requests were concerned. As a consequence, the appeal of the patentee was admissible. See also T 1668/14.

If the appellant submits that the decision under appeal is incorrect, then the statement setting out the grounds of appeal must enable the board to understand immediately why the decision is alleged to be incorrect and on what facts the appellant bases its arguments, without first having to make investigations of its own (J 10/11, see also T 220/83, OJ 1986, 249, and T 177/97; affirmed by numerous decisions, see for example T 573/09 and T 918/17).

Exceptionally, it has been acknowledged that the requirement for admissibility may also be regarded as satisfied if it is immediately apparent upon reading the decision under appeal and the written statement of grounds that the decision should be set aside (see J 22/86, OJ 1987, 280).

In T 343/16 the board stated that references to the statement of grounds of other appellants were permissible. In the case in hand opponent 1 had referred to its notice of appeal and in support of its request that the patent be revoked, invoked the statement of grounds of appeal of appellant 2, which was stated to be incorporated by reference. The board held that the appeal by opponent 1 was admissible.