According to the wording of
Art. 82 EPC, the requirement of unity of invention has to be satisfied not only by the patent application as filed but also by the patent application at later stages of the patent granting procedure, i.e. before the examining division, up until grant of the patent.
R. 64(2) EPC (
R. 46(2) EPC 1973; unchanged in substance) refers to the possibility that the examining division might disagree with the search division concerning lack of unity of a particular patent application and that then the examining division's opinion is decisive in that the latter may order refund of any further search fee at the applicant's request. It lies within the discretion given to the examining division to decide that a patent application lacks unity of invention within the meaning of
Art. 82 EPC, even if the search division did not raise a similar objection under
R. 64(1) EPC (
R. 46(1) EPC 1973; unchanged in substance) (
T 178/84, OJ 1989, 157).