a) Principles 

Art. 69 EPC and its Protocol are to be applied in proceedings before the EPO whenever it is necessary to determine the protection conferred. In this context, the national laws of the contracting states relating to infringement should not be considered. Rather the protection conferred by a patent is determined by the terms of the claims, and in particular by the categories of the claims and their technical features, in accordance with Art. 69(1) EPC and its Protocol (G 2/88, OJ 1990, 93; see also e.g. T 81/03, T 547/08, T 1832/17 and T 970/17, all with reference to G 2/88, and in this chapter II.E.2.3.1b)).

In T 325/95 the board pointed out that the assumption that the extent of protection referred to in Art. 123(3) EPC 1973 would depend not only on the actual wording of the claims, but also on their validity in view of the prior art, was not supported by the explicit statement in Art. 69 EPC 1973 that "the extent of the protection conferred by a European patent ... shall be determined by the terms of the claims". The appellant's submissions also implied that claims amended in opposition proceedings should always have a counterpart in the set of claims as granted. The board noted that this was not in line with the consistent case law of the EPO either. Attention was drawn for instance to decision G 2/88 (OJ 1990, 93), which ruled that replacement of a granted claim to a compound or composition by a claim directed to a new use of the compound or composition was admissible under Art. 123(3) EPC 1973.