In T 1816/11, the sole reason for the examining division's refusal to admit the main request had been that it did not meet the requirements of Art. 84 and 56 EPC. The board held that, in such cases, where the discretionary decision had been taken on substantive rather than procedural grounds, the criteria established in G 7/93 could not apply (likewise T 820/14, T 556/13 and T 971/11). Rather, the substantive assessment (of clarity, inventive step, etc.) underlying the decision was fully open to review, as this went to the very essence of the boards' power of review.

In T 2342/13, as to the examining division's reason for not admitting the auxiliary request, namely a prima facie lack of inventive step, the board considered that a question relating directly to the compliance of a request with a provision of substantive patent law was to be assessed by the board itself and that on such a point there was no latitude for deferring to the view of the department of first instance (cf. T 1816/11, similar T 2343/13).

The board in T 1820/13 added that, although an opposition division's exercise of discretion could, as a rule, be reviewed only to a limited extent, i.e. only for abuse or errors, that could not mean that any substantive issues underlying its resulting decision were not open to review by the boards. Such issues went to the very essence of the boards' power of review and so they were called on to use their own discretion under Art. 12(4) RPBA 2007 (see T 1816/11). Thus, their review of an exercise of discretion had to include checking any underlying prima facie examination, for example as to whether it was vitiated by manifest errors.

In T 47/14, the appellant did not dispute that the opposition division had exercised its discretion in accordance with the right criteria but rather challenged its substantive assessment of a citation. It set out why it considered the assessment to be wrong and so to have led to an erroneous evaluation of the citation's relevance and an unjustified refusal to admit it. At issue therefore was whether the opposition division had exercised its discretion improperly as a result of being mistaken as to the citation's technical relevance. The board found that it was certainly open to it to review the substantive basis for an opposition division's exercise of discretionary decision if the resulting decision was manifestly erroneous (see T 109/08).