The responsibilities and composition of boards are laid down in Art. 21 EPC. In G 2/90 (OJ 1992, 10) the Enlarged Board made it clear that under Art. 21(3)(c) EPC 1973, the Legal Board of Appeal was competent only for appeals against decisions taken by an examining division consisting of fewer than four members and which did not concern refusal of the application or grant. In all other cases, i.e. those covered by Art. 21(3)(a) EPC 1973, Art. 21(3)(b) EPC 1973 and Art. 21(4) EPC 1973, the technical boards were competent. The provisions of Art. 21(3) and (4) EPC 1973 governing responsibilities and composition were not affected by R. 9(3) EPC 1973.

In G 3/03 (OJ 2005, 343), the Enlarged Board of Appeal held that in the event of interlocutory revision under Art. 109(1) EPC 1973, the department of first instance whose decision had been appealed was not competent to refuse a request of the appellant for reimbursement of the appeal fee. It was the board of appeal which would have been competent under Art. 21 EPC 1973 to deal with the substantive issues of the appeal if no interlocutory revision had been granted which was competent to decide on the request.

In G 1/11 (OJ 2014, A122) the Enlarged Board of Appeal held that a technical board of appeal was competent to hear an appeal against an EPO examining division's decision – taken separately from its decision granting a patent or refusing the application – not to refund search fees under R. 64(2) EPC.