a) Principles 

Pursuant to the non-exhaustive list of criteria in Art. 12(4), fifth sentence, RPBA, the boards are to exercise their discretion in view of, inter alia, the complexity of the amendment, the suitability of the amendment to address the issues which led to the decision under appeal, and the need for procedural economy.

As a further criterion, the boards have considered whether the submissions on appeal should have been filed earlier or whether – on the contrary – they were filed at the first opportunity, i.e. could be justified as a legitimate reaction to late developments in the proceedings leading to the decision under appeal. See e.g. T 121/20, T 864/20, T 3240/19 and T 3248/19, which partly refer to Art. 12(6) RPBA in this context, as well as T 73/20, which additionally refers to the requirement in Art. 12(4), third sentence, RPBA according to which the party shall inter alia provide reasons for submitting the amendments in the appeal proceedings.

Other factors taken into account by the boards when exercising their discretion include whether the party's case takes account of the primary object of the appeal proceedings to review the contested decision in a judicial manner (see e.g. T 1963/20), and whether it would seem appropriate to defer dealing with a citation until any subsequent revocation proceedings, albeit without giving this factor the same importance as the criteria in Art. 12(4) RPBA (T 1657/20).

The decisions summarised in this sub-chapter are reported under the heading of one of these criteria but their assessment was usually based on an overall consideration of several factors. See e.g. T 3240/19, T 3248/19, T 121/20, T 868/20, T 869/20, T 1516/20, T 1617/20, T 1821/20).

Whether the boards have discretion to exclude submissions which form part of the appeal proceedings under Art. 12(2) RPBA is debatable. In many decisions the boards have considered that there is no legal basis for excluding submissions (such as prior art documents) from the appeal proceedings which had been admitted into the proceedings by the opposition division (see e.g. T 617/16, T 2337/16, T 449/21). In other decisions the boards have held that they review such discretionary decisions, albeit only in a limited way (see e.g. T 2055/20, with reference to CLB, 10th edn. 2022, V.A.3.4.1.b) and to G 7/93, OJ 1994, 775).