5.2. The purpose of Rule 137(5) EPC

The wording of R. 137(5), first sentence, EPC is the same as that of R. 86(4) EPC 1973. R. 86(4) EPC 1973 (with effect from 1 June 1995), was intended to prevent amendments of the application which circumvent the principle that a search fee must always be paid for an invention presented for examination. The board in T 274/03 explained that R. 86(4) EPC 1973 stopped applicants switching to unsearched subject-matter in the reply to a communication from the examining division and made means available for the EPO to react when different subject-matter was claimed not simultaneously but in sequence as was the case when the applicant drops the existing claims and replaces them with originally non-unitary subject-matter extracted from the description. See also T 442/11, T 509/11, T 1285/11, T 2334/11, T 145/13, T 1485/13, T 820/15.

In T 443/97 the board stated that R. 86(4) EPC 1973 (now R. 137(5) EPC) concerned examination proceedings, and particularly those cases in which no further search fees requested by the search division for non-unitary subject-matter had been paid by the applicant. The purpose of R. 86(4) EPC 1973 was to exclude any amendment which circumvented the principle according to which a search fee must always be paid for an invention presented for examination. The board noted that unity of invention was a requirement of an administrative nature and that the administrative purposes of this requirement were fulfilled when the examination procedure had been concluded, i.e. when the patent had been granted (see G 1/91, OJ 1992, 253). Therefore, R. 86(4) EPC 1973 was not relevant for the opposition case in hand.