If the tests set out in F‑VI, 2.2 are not satisfied in relation to a particular previous application, then the effective date of the subject-matter of the claim in question will either be the filing date of the earliest application which does provide the required disclosure and of which the priority is validly claimed (see G 3/93) or, in the absence of such, will be the date of filing of the European application itself (or the new date of filing if the application has been re-dated under Rule 56).
Source: http://www.epo.org/law-practice/legal-texts/html/guidelines/e/f_vi_2_3.htm
Date retrieved: 17 May 2021