Exceptional circumstances in the appeal procedure

Neither Article 13 (2) RPBA 2020 nor the explanatory remarks contain an explanation of how to generally determine whether circumstances are "exceptional". However, the explanatory remarks of RPBA 2020 cite as an example of such "exceptional" circumstances the case where the Board of Appeal has raised an objection for the first time in a notification. In this case, the changed basis of the appeal proceedings justifies an amendment of the party’s submission. The question of whether, conversely, the basis of the appeal proceedings is also changed by an amended submission thus represents a possible criterion to be used for the assessment of the exceptional nature of the circumstances (EPO Board of Appeal 26/11/2021, T 988/17).