In T 182/88 (OJ 1990, 287) and T 166/86 (OJ 1987, 372) the boards decided that a separate set of claims submitted at a late stage in the proceedings was admissible under the particular circumstances. They added that the EPO's user-friendly reputation should clearly be excluded from consideration during the exercise of any discretion by the EPO. The showing of consideration towards parties before the EPO should not be confused with the proper exercise of discretion according to the law. It was also held that when a decision hinged on the exercise of discretion, the reasons should be given.
In T 309/09 the board doubted that the number of auxiliary requests could generally be considered a factor on the basis of which their admission under R. 137(3) EPC could properly be denied outright. Whilst it did not wish to rule out that a large number of auxiliary requests might be a sufficient reason in specific cases, it decided that the question could be left unanswered in the case in hand, as in any event six auxiliary requests could not automatically be considered excessive. Nor did it have to consider whether a lack of convergence among the requests was relevant in this connection, because the contested decision did not contain any explicit analysis of specific cases which might support such a conclusion, even though any convergence criterion applied would at any rate have had to be assessed separately for each individual request. The board concluded that the examining division had been entitled to exercise discretion and had done so in accordance criteria which were essentially correct in the light of G 7/93, but that, contrary to R. 111(2) EPC, it had failed to give adequate reasons in support of its exercise of discretion in the contested decision. Discretionary decisions could not be taken arbitrarily and – like all decisions open to appeal – had to be substantiated.
In T 246/08 the board stated that it is the established jurisprudence of the boards of appeal that the power of the examining division to consent to amendments under R. 137(3) EPC is a discretionary power that has to be exercised after considering all the relevant factors of the specific case and balance in particular the applicant's interest in obtaining an adequate protection for his invention and the EPO's interest in bringing the examination to a close in an effective and speedy way. Moreover, the exercise of a discretionary power has to be reasoned, otherwise it would be arbitrary. It followed that a refusal of consent to amend made in advance of any amendment being submitted could not be a reasonable exercise of discretion pursuant to R. 137(3) EPC. Indeed it was ipso facto a substantial procedural violation since it risked deterring an applicant from making an amendment which could not reasonably have been forbidden. See also T 872/90.
In T 233/12 the board pointed out that the criterion that an amended set of claims is prima facie not allowable is, in general, an accepted principle (amongst others) to be taken into account in the assessment of whether consent under R. 137(3) EPC should be given to the amendment. While a prima facie finding that a claim is not allowable may, by its very nature, be justified in briefer terms than a fully reasoned conclusion, the reasons for a prima facie finding may not be so short as to reduce the finding to a mere allegation. Moreover, the amount of reasoning required to justify a prima facie finding was amongst the parameters which the examining division had to balance in view of the circumstances of each individual case when exercising its discretion. In particular, if an applicant files an amendment together with arguments as to why the amendment, in its view, satisfies a particular requirement of the EPC, the examining division cannot merely assert the contrary without giving an indication as to why the applicant's argument failed. That is, a prima facie finding must not simply ignore the arguments on file which appear to directly contradict it.