In T 828/93 the board stated that it followed from Art. 88(3) EPC 1973 that different priorities (including no priority, i.e. only the date of the European application) could be conferred on different parts of a European application. All that had to be checked was whether the subject-matter to be compared with the prior art, i.e. the subject-matter of the independent patent claims, corresponded to the disclosure of the documents of the priority application as a whole (see Art. 88(4) EPC 1973). Only one (or, as the case may be, no) priority could be conferred on each claimed subject-matter as a whole, in so far as the subject-matter was defined by the given elements as a whole. This subject-matter as a whole represented the invention, which either corresponded to the disclosure of a priority application or not.
T 132/90 concerned a case in which claim 1 of the contested patent contained a feature B not disclosed in the Swiss priority document. The board held that a priority right therefore subsisted only with regard to part of the subject-matter of the claim, i.e. claim 1 without feature B, but not with regard to the subject-matter of that claim as a whole. The part of the subject-matter entitled to priority did not involve an inventive step. The subject-matter as a whole of claim 1 of the European application, which only had the priority status of the filing with the EPO, was no longer new because the patent proprietors had published all its features after filing the Swiss application.
In T 127/92 a European patent application claimed the priority of two German utility models, which had been published during the priority interval (documents D1 and D2). The board of appeal took the view that priority had been validly claimed from D1 for claim 1 and several dependent claims. It was necessary to establish whether those sub-claims that also contained elements not disclosed in D1 were entitled to claim partial priority from D1 for the subject-matter of claim 1 contained within them. On the basis of the principles developed in G 3/93 (OJ 1995, 18), the board concluded that D1 and D2 formed part of the state of the art in respect of these claims and that, consequently, the subject-matter of these claims no longer involved an inventive step. The patent proprietor therefore deleted them.