In T 87/88 (OJ 1993, 430) the board noted that the Enlarged Board of Appeal had ruled that when the EPO carries out an international search, an international application may also be considered, under Art. 17(3)(a) PCT, not to comply with the requirement of unity of invention "a posteriori", i.e. after prior art is taken into consideration and a provisional opinion on novelty and inventive step is thereby formed (G 1/89, OJ 1991, 155; G 2/89, OJ 1991, 166). This principle applied equally when carrying out a European search (Art. 92 EPC 1973) because in both cases the searches and search reports were virtually identical. The appellants' objection that a search division was not entitled to decide that the claimed invention lacked unity "a posteriori" as well was therefore unfounded.
In T 94/91 it was added that Art. 82 EPC 1973 clearly provided that European patent applications must satisfy the criteria of unity of invention without any restriction. There was no difference in the EPC 1973 between "a priori" and "a posteriori" lack of unity. It was of no importance whether the nonunity appeared immediately or only in view of a document found during the search or the examination.
In T 544/88 (OJ 1990, 429) the board ruled that if an applicant, in response to an objection of lack of unity under Art. 82 EPC 1973, filed new claims allegedly relating to an invention meeting the unity requirement, examination should be continued even if the other application documents had not been limited to the subject-matter of those claims. However, the examining division might request the applicant to bring the description and drawings into line with the valid claims (R. 27(1)(d) EPC 1973 as in force until 31.5.1991; cf. subsequent R. 27(1)(c) EPC 1973, now R. 42(1)(c) EPC) and to delete from the patent documents those parts of the description and drawings which did not refer to claimed inventions (R. 34(1)(c) EPC 1973). It would then be necessary to check in each individual case whether such adjustments ought to be deferred until allowable claims were submitted.