Even under the assumption that the information given by a technical board of appeal on a decision of the Enlarged Board of Appeal was unclear, parties are deemed to know the case law, at least when represented by an authorised representative. Thus, a party cannot plead lack of such knowledge as an excuse (R 4/09).

In R 17/09 the Enlarged Board held that reference to decisions in a decision, even decisions not cited to the party earlier in writing or at the oral proceedings, could not constitute a fundamental violation of the right to be heard.

In R 9/14 the Enlarged Board held that a qualified professional representative can be assumed to be familiar with the analytical sequence of the problem-solution approach. Special guidance from the board is not necessary. Likewise in R 5/16 the Enlarged Board found that a party to appeal proceedings and its professional representative should be aware of the methodology established in the case law of the boards of appeal for examining inventive step and should be prepared to submit its relevant arguments in this respect.

In R 4/16 the Enlarged Board held that the boards might sometimes be obliged to back up a reference they made to established case law, but the onus could not be on them always to seek out specific decisions that a party had not cited in support of a position it was arguing. Were a board to do so in opposition proceedings, that would amount to its making the case for one of the parties itself, to the detriment of the other party and contrary to its duty of impartiality.