In T 1653/12 the board pointed out that the applicant's statement did not provide a basis for the search examiner to perform a meaningful search. The particular wording used therein ("and/or") left it entirely open which of the two alternatives claimed should be searched. Hence, it was plausible that a meaningful search could not be made.
Source: http://www.epo.org/law-practice/legal-texts/html/caselaw/2019/e/clr_iv_b_4_1_3_c.htm
Date retrieved: 17 May 2021