The 2000 and 2007 Notices (points 2.5 and 2.3 respectively) state that any request to set another date for oral proceedings should indicate why another representative cannot stand in for the one unable to attend. This means that if and when the board is satisfied that the representative is prevented from attending, it must therefore be considered whether another representative, who does not have to be from the same firm, can substitute for the prevented representative (T 699/06, T 861/12). If the appellant has signed a general authorisation to a law firm, the representative has to provide convincing reasons why no other representative of this firm could substitute for the representative (T 518/10).

In T 1067/03 the representative requested that the oral proceedings be postponed because of a prior appointment for a medical operation. The representative said that his client was opposed to a change of representative on the grounds that, in addition to the appeal in question, a further opposition and a patent infringement case were pending which together formed an intricate ensemble. In the board's opinion, these circumstances justified postponing the oral proceedings.

In T 1011/09 the board found that the statement prescribed in point 2.5 of the 2000 Notice had to contain more than a mere expression by the appellant of its general desire to be represented at oral proceedings by its usual representative, and that specific reasons had to be given as to why it was impossible, or at least unreasonably difficult, to arrange a replacement for the representative unable to attend (citing T 1080/99, OJ 2002, 568; T 1067/03; T 300/04; T 178/03). Moreover, point 2.5 of the 2000 Notice required that the reasons had to go beyond referring to the additional cost of replacing a representative. Such costs had to be accepted, at least up to a reasonable amount, given the new representative's need to familiarise himself with the case. See also T 861/12.

In T 1610/08 the board held that point 2.1 of the 2007 Notice, which lists pre-booked holidays as a potential reason for postponement, had to be balanced against point 2.3 of the Notice, according to which every request should explain why the representative could not be substituted. The board was of the opinion that the circumstances indicated by the respondent with respect to point 2.3 of the Notice (namely, the representative had a long-standing relationship of trust with the client, he was the only one with knowledge of the client's business or technology, and his knowledge of the earlier proceedings before the opposition division was unique and irreplaceable) were in fact common to all cases in which substitution was involved. In the board's view, only extraordinary circumstances, i.e. those which were not common to every case of substitution, should be accepted.

In T 861/12 the board held that the opponent violated the principle of good faith by withdrawing the authorisation of five of the six representatives originally authorised, despite being unable to show a legitimate interest in doing so and knowing full well that the remaining professional representative could not attend oral proceedings on the date scheduled. This withdrawal of the authorisation could not be considered under point 2.3 of the 2007 Notice.