e) Indication of evidence 

Assessing the evidence is part of the process of ascertaining whether the opposition is well founded in substance (T 234/86, OJ 1989, 79). Thus, in T 353/06 the board identified the appellants' arguments for the inadmissibility of the opposition as concerning the corroborative value of the facts and evidence, rather than a failure to indicate such facts and evidence in support of the grounds of opposition.

In T 426/08 too, the board, citing T 234/86 and T 538/89, stressed that R. 55(c) EPC 1973 did not require that the indicated evidence be put on file within the period for opposition. However, the board considered that the content of evidence merely referred to within the opposition period but not produced until after it could not, for the purpose of examining admissibility, be taken into account either as an indication of facts or evidence or as proof of facts. On the indication of evidence in the context of public prior use, see in this chapter IV.C.2.2.8i) below.

In T 1408/19 the board observed that R. 76(2)(c) EPC merely required an indication of the facts and evidence presented in support of the argued grounds for opposition, but that not necessarily every piece of evidence need already be presented along with the notice of opposition. It should also be sufficient if the indications given in the notice of opposition permitted the substantive content of the evidence offered to be established only at a later stage, provided that this substantive content could be established without undue effort and still within a reasonable time. In the case in hand the patent proprietor argued that the opposition was insufficiently substantiated and therefore was not admissible due to the erroneous citation of the publication number of document E2 which meant it was not possible to identify it; unacceptable independent enquiries and further investigations would therefore have been necessary to enable the proprietor to understand the objections raised. According to the board, the facts and evidence submitted in accordance with R. 76(2)(c) EPC were sufficient for the ground of opposition to be correctly understood by the opposition division and the proprietor.