Under R. 106 EPC, a petition under Art. 112a(2)(a) to (d) EPC is only admissible where an objection in respect of the procedural defect was raised during appeal proceedings and dismissed by the board, except where such objection could not be raised.
Source: http://www.epo.org/law-practice/legal-texts/html/caselaw/2019/e/clr_v_b_3_6.htm
Date retrieved: 17 May 2021