In R 21/11, so far the only allowable petition based on R. 104(b) EPC, the petitioner (patentee) claimed that the board had decided on the appeal without deciding on a request for admission of a second expert testimony filed by fax. The Enlarged Board found that R. 104(b) EPC was a specific manifestation of the right to be heard which applied regardless of whether the party's submission might have persuaded the board. The argument that the undecided request was irrelevant because its admission would not have made a difference could only be accepted if it could be shown that all aspects "lost" as a result of its non-admission had been taken into account in the decision under review. According to the Enlarged Board, the procedural defect asserted by the petitioner constituted an infringement of its right to be heard, both under Art. 112a(2)(d) EPC in conjunction with R. 104 EPC and under Art. 112a(2)(c) EPC in conjunction with Art. 113(1) EPC. While the petitioner had argued that this infringement consisted in the board's failure to take account of the second testimony in its decision, the Enlarged Board saw the infringement in the board's failure to consider the request for its admission. Had that request been granted, it could have influenced the outcome. There was therefore a causal link between the denied opportunity to comment and the board's decision (see in this chapter V.B.4.3.2). The contested decision was set aside.