The Enlarged Board of Appeal has clarified the position for potential parties in other possible petition proceedings, in particular with regard to the two distinct stages provided for in Art. 112a EPC and R. 109 EPC (R 5/08). R. 109(1) EPC provides that, "In proceedings under Art. 112a EPC, the provisions relating to the proceedings before the Boards of Appeal shall apply, unless otherwise provided". As regards the procedure for the first stage of petition proceedings, there are indeed such measures "otherwise provided" namely R. 109(2) and (3) EPC. Under R. 109(2) EPC, a panel of three members of the Enlarged Board examines all petitions for review and rejects all those which are clearly inadmissible or unallowable (unanimity is required). Those not rejected are then considered by five members of the Enlarged Board (R. 109(2)(b) EPC). The preliminary panel of three members decides without the involvement of other parties and on the basis of the petition (R. 109(3) EPC).
The effect of these provisions is that parties other than the petitioner are not to be involved in the first stage of petition proceedings, and so long as they are not involved they have no right to be heard. The travaux préparatoires stress the need for a quick screening process to be conducted by a three-member panel of the Enlarged Board in order to reject petitions which clearly cannot succeed. The legislator intended to benefit parties other than the petitioners by not requiring them to take any steps in response to a petition until the Enlarged Board was satisfied that it was not to be rejected as clearly inadmissible or unallowable. Non-petitioner parties, although not summoned, could nonetheless attend oral proceedings, which are public.