Where a document relating to potential prior art according to Art. 54(3) is referred to in the search opinion, two situations may arise, depending on whether or not the search division can conclusively establish that said prior-art document has an earlier relevant date than that of the application. If so, the search division raises an objection under Art. 54(3). If not, it assumes that any priority which cannot be checked is valid. This leads to two different scenarios:
Where there are also "P" documents cited in the search report and these are not potential Art. 54(3) documents (because they are not international or European patent applications), these documents may constitute prior art under Art. 54(2) and thus be relevant for the assessment of novelty and inventive step in so far as the priority of the application is not valid. Where the priority of the application can be checked, the search division checks the priority and makes objections in the search opinion based on the "P" documents if the priority is not valid. If the priority of the application cannot be checked, it is assumed to be valid and no objection is raised in the search opinion.
The issue of the validity of the priority claim(s) then needs to be reviewed in examination (see F‑VI, 2).
Source: http://www.epo.org/law-practice/legal-texts/html/guidelines/e/b_xi_4_1.htm
Date retrieved: 17 May 2021