In T 653/91 the board held that if, having been summoned to oral proceedings, a party did not wish to attend such proceedings, both the board (through its Registrar) and any other parties to the proceedings should be notified in writing of this fact as early as possible before the appointed day. Except in special circumstances, telephone communications concerning such matters were inappropriate, especially in inter partes proceedings.
In T 930/92 (OJ 1996, 191) the board also pointed out that there was an equitable obligation on every party summoned to oral proceedings to inform the EPO as soon as it knew that it would not attend as summoned. This was the case whether or not that party had itself requested oral proceedings, and whether or not a communication had accompanied the summons to oral proceedings.
In T 692/00 the board held that for the appellant (proprietor) to announce shortly before the appointed date for oral proceedings that it might or might not attend while maintaining its request for oral proceedings could only be an abuse of procedure.
In T 69/07 the respondent had requested oral proceedings but did not appear at the oral proceedings at the appointed time. The board noted that, in accordance with Art. 6 of the Code of Conduct of Members of the epi, of which the representative is obligatorily a member, the members are required to act courteously in their dealings with the EPO. The representative of the respondent had had sufficient time to inform the board of its intended non-appearance at the oral proceedings. This would have avoided keeping the other party and the board first of all courteously waiting for the representative in case he had unintentionally been delayed, and then obliging the registrar of the board to carry out enquiries to establish if the representative intended to attend the oral proceedings (see also T 1760/09). In similar cases, the boards held that the actions of the representative were "reprehensible" (T 954/93, T 69/07).
In all these cases, an apportionment of costs in favour of the attending party could be justified, see Chapter IV.C.7.2.2 "Acts or omissions prejudicing the timely and efficient conduct of oral proceedings".