R. 63(1) and (2) EPC (incomplete search) (former R. 63 EPC; R. 45 EPC 1973) have been amended by decision of the Administrative Council CA/D 3/09 of 25 March 2009 (OJ 2009, 299), which entered into force on 1 April 2010.

Under R. 63(1) EPC if the EPO considers that the European patent application fails to such an extent to comply with the EPC that it is impossible to carry out a meaningful search regarding the state of the art on the basis of all or some of the subject-matter claimed, it shall invite the applicant to file, within a period of two months, a statement indicating the subject-matter to be searched. See T 1653/12.

According to R. 63(2) EPC if the statement under paragraph 1 is not filed in due time, or if it is not sufficient to overcome the deficiency noted under paragraph 1, the EPO shall either issue a reasoned declaration stating that the European patent application fails to such an extent to comply with the EPC that it is impossible to carry out a meaningful search regarding the state of the art on the basis of all or some of the subject-matter claimed or, as far as is practicable, draw up a partial search report. The reasoned declaration or the partial search report shall be considered, for the purposes of subsequent proceedings, as the European search report. See T 1653/12.

In the ideal case, the applicant's statement removes completely the deficiencies under Art. 84 EPC and a complete search report can be drawn up. Alternatively, the partial search report will be drawn up in the light of the applicant's submissions, so that it will be up to the applicant to delimit the subject-matter to be searched.

R. 63 EPC enables the applicant to submit statements more clearly defining the subject-matter to be searched in cases where a normal search cannot be carried out. However, because the search report should, as a rule, be drawn up in time for publication together with the application further processing in respect of the period referred to in proposed R. 63(1) EPC will be excluded. This implies that re-establishment of rights will be possible.

In T 1242/04 (OJ 2007, 421) the board held that R. 45 EPC 1973 applies to cases which do not comply with the provisions of the EPC to such an extent that it is not "possible" to carry out a "meaningful search" into the state of the art on the basis of all or some of the claims. Thus a R. 45 EPC 1973 declaration is allowed only where a search is not possible. In other cases the search division draws up a partial search report, "so far as is practicable". R. 45 EPC 1973 relates only to the practicability of a search and not to the potential relevance of its results in subsequent substantive examination.

In T 1653/12 the board noted that T 1242/04 dealt with former R. 45 EPC 1973, which has a different wording from current R. 63 EPC. Since T 1242/04 dealt with a case, in which no invitation of the search division under R. 63(1) EPC and no response thereto was present, the reasons of that decision were not directly applicable to the case in hand. However, both decisions stated that fundamental clarity problems might make it impossible to carry out a meaningful search. The discrepancy between the claims and description was such a fundamental clarity problem.