In addition to the reasons discussed in B‑VIII, 1, an invitation under Rule 63(1) and subsequent limitation of the search under Rule 63(2) may also result from the application not meeting the relevant requirements of the EPC to such an extent that a meaningful search of the claims, or of some of the claims, or of part of a claim, is impossible. In such cases, the search division should apply the procedure under Rule 63 (see B‑VIII, 3.1 to B-VIII, 3.4, and OJ EPO 2009, 533).
Rule 63 relates only to the practicability of the search and not to the potential relevance of its results in subsequent examination. Even if a search were not to produce any result that could be used in examination proceedings, a search cannot be refused by reference to Rule 63 (see T 1242/04).
What is or is not "meaningful" is a question of fact for the search division to determine. Its finding may change in the light of any reply from the applicant to the invitation under Rule 63(1) (see B‑VIII, 3.2). The exercise of the search division's discretion will depend upon the facts of the case. A restriction of the search must be carefully considered. There are cases where a search is rendered de facto impossible by the failure to meet the prescribed requirements of the EPC, for example a fundamental lack of clarity or the absence of any technical character whatsoever. The word "meaningful" should be construed reasonably. It should not be construed in such a way that Rule 63 is invoked simply because a search is difficult or does not provide results that are significant for subsequent examination proceedings.
As there is no legal provision providing that an applicant must formulate the application in such a way as to make an economical search possible, "reasons of economy" cannot be used as a reason, or part of a reason, for issuing an incomplete search report (see also T 1020/98).
A number of non-limiting examples will illustrate where Rule 63 may find application:
One example would be the case of a broad or speculative claim supported by only a limited disclosure covering a small part of the scope of the claim. This could be the case if the broadness of the claim is such as to render a meaningful search over the whole of the claim impossible, and where a meaningful search could only be performed on the basis of the narrower, disclosed invention. This may mean a search of the specific examples. In such a case, it will often be de facto impossible to do a complete search of the whole of the claim at all, because of the broad drafting style. Accordingly, the procedure under Rule 63(1) may be applied (see B‑VIII, 3.1 to B-VIII, 3.4). Here, the requirements underlying the application of Rule 63 would be those of sufficiency of disclosure and support set out in Art. 83 and Art. 84 (see F‑III, 1 and F-III, 2, and F‑IV, 6). The examiner should however bear in mind that the requirements under Art. 83 and Art. 84 concerning sufficiency of disclosure and support should be seen in relation to the person skilled in the art.
An example would be where there are so many claims, or so many possibilities within a claim, that it becomes unduly burdensome to determine the matter for which protection is sought (however, for the case of multiple independent claims in the same category see B‑VIII, 4). A complete search (or any search at all) may de facto be impossible. Again, the application of Rule 63 and the issuing of a subsequent incomplete search report (according to the procedures defined in B‑VIII, 3.1 to B-VIII, 3.3) or a declaration of no search may be appropriate, on the grounds that the lack of conciseness of the claim(s) is such as to render a meaningful search impossible (see Art. 84; F‑IV, 5).
An example would be where the applicant's choice of parameter to define his invention renders a meaningful comparison with the prior art impossible, perhaps because the prior art has not employed the same parameter, or has employed no parameter at all. In such a case, the parameter chosen by the applicant may lack clarity (see Art. 84; F‑IV, 4.11). It may be that the lack of clarity of the parameter is such as to render a meaningful search of the claims or of a claim or of a part of a claim impossible, because the choice of parameter renders a sensible comparison of the claimed invention with the prior art impossible. If so, the application of Rule 63 and the issuing of a subsequent incomplete search report (or, in exceptional cases, no search at all) under Rule 63(2) (according to the procedures defined in B‑VIII, 3.1 to B-VIII, 3.3) may be appropriate, the search possibly being restricted to the worked examples, as far as they can be understood, or to the way in which the desired parameter is obtained (any response from the applicant to the invitation under Rule 63(1) being taken into account in determining the subject-matter to be searched to the extent indicated in B‑VIII, 3.2).
These examples are not exhaustive (see also B‑VIII, 6). The basic principle is that there should be clarity and openness both for the applicant and for third parties as to what has and what has not been searched.