The obligation to provide adequate reasoning in a decision in accordance with R. 111(2) EPC (R. 68(2) EPC 1973) is closely linked to the principle of the right to be heard under Art. 113 EPC (T 1340/10). A failure to do so is to be considered a substantial procedural violation justifying the reimbursement of the fee for appeal (see among many other cases T 493/88, OJ 1991, 380; T 522/90; T 392/91; T 142/95; T 278/00; T 571/03; T 897/03; T 1366/05; T 1612/07; T 87/08; T 353/11; T 2366/11; T 129/14 and T 679/14).

In T 75/91 the board stated that the impugned decision enabled the reader to follow a line of argument for refusing the application. Whether these reasons were convincing and had to be accepted by the board had nothing to do with a procedural violation. See also T 698/10, where the board added that the examining division was under no obligation to explicitly address every argument presented by the applicant as long as the reasoning given enabled the appellant and the board to examine whether the decision was justified or not. See also chapter III.B.2.4. "Consideration of the parties' arguments, submissions and evidence".

In T 2340/13 there was a discrepancy between what was stated in the "Summary of facts and submissions" of the written decision of the opposition division, where it was stated that, inter alia, Art. 123(3) EPC was discussed in detail, and the minutes, which although very detailed, did not mention any discussion concerned with Art. 123(3) EPC. Neither was there any discussion of this matter in the "Grounds for the decision", except that the title above point 3 read "Added subject-matter (Art. 100(c), 123(2), 123(3) EPC)". The board found that if the matter had been discussed, the opposition division should properly have given an indication thereof in the minutes and indicated in the decision whether and why Art. 123(3) EPC was regarded as being complied with. The board held that the omission of any reasons in respect of Art. 123(3) EPC was not only a violation of R. 111(2) EPC but also of Art. 113(1) EPC.

In T 2282/17 the board held that where a decision only refers to one or more previous communications, leaving it to the board and the appellant to speculate as to which of the reasons given by the examining division might be essential to the decision to refuse the application, it does not meet the requirements of R. 111(2) EPC. Since the examining division's decision clearly contravened R. 111(2) and Art. 113(1) EPC, and since the appellant had to appeal in order to obtain a fully reasoned decision, the board found it was equitable to reimburse the appeal fee pursuant to R. 103(1)(a) EPC.

For cases concerning the obligation under R. 111(2) EPC, R. 68(2) EPC 1973, see chapter III.K.3.4. "Reasons for the decision", and in particular chapter III.K.3.4.4.