In G 2/88 (OJ 1990, 93) the Enlarged Board stated that a change of category of granted claims in opposition proceedings was not open to objection under Art. 123(3) EPC 1973, if it did not result in extension of the protection conferred by the claims as a whole, when they were interpreted in accordance with Art. 69 EPC 1973 and its Protocol. In this context, the national laws of the contracting states relating to infringement should not be considered, for there was a clear distinction between the protection which was conferred and the rights which were conferred by a European patent. The protection conferred by a patent was determined by the terms of the claims (Art. 69(1) EPC 1973), and in particular by the categories of such claims and their technical features. In contrast, the rights conferred on the proprietor of a European patent (Art. 64(1) EPC 1973) were the legal rights which the law of a designated contracting state might confer upon the proprietor. In other words, in general terms, determination of the "extent of the protection conferred" by a patent was a determination of what was protected, in terms of category plus technical features; whereas the "rights conferred" by a patent were related to how such subject-matter was protected. When deciding upon the allowability of an amendment involving a change of category, the considerations were, in principle, the same as when deciding upon the allowability of any other proposed amendment under Art. 123(3) EPC 1973.