In T 278/00 (OJ 2003, 546) the board held that the reasoning of a decision under appeal must be taken as it stands. The requirements of R. 68(2) EPC 1973 could not be construed in such a way that, in spite of the presence of unintelligible and therefore deficient reasoning, it was up to the board or the appellant to speculate as to what might be the intended meaning of it. The board had to be in a position to assess on the basis of the reasoning given in the decision under appeal whether the conclusion drawn by the first instance was justified or not. That requirement was not satisfied when the board was unable to decide which of the various inconsistent findings indicated in and justifying the decision under appeal were correct and which were false (see also T 316/05).
In T 70/02 the board found that simply stating "no convincing arguments have been found in your letter" in response to letters in which the objections put forward were exhaustively discussed by the applicant, did not comply with R. 68(2) EPC 1973. Whilst reasoning did not mean that all the arguments submitted should be dealt with in detail, it was a general principle of good faith and fair proceedings that reasoned decisions should contain at least some reasoning on crucial points of dispute, in order to give the party concerned a fair idea of why its submissions were not considered convincing and to enable it to base its grounds of appeal on relevant issues.
The mere summary of a party's submissions does not constitute sufficient reasoning (T 1366/05 and T 534/08). In the latter case it was not clear from the wording of the contested written decision why the opposition division had come to its conclusion, whether or not the opposition division had adopted the respondent's arguments entirely, or whether or not it had had its own objections.