5.13.6 Public prior use
The boards began early on in their case law to set strict standards for the admissibility of late-filed evidence of public prior use by the opponent. On the basis of Art. 114(2) EPC 1973, they refused to include late-filed evidence in the proceedings where, in the specific circumstances, there had been an abuse of procedure and a breach of the principle of good faith. In such cases they chose to refrain from examining the potential relevance of the submission (see T 17/91; T 534/89, OJ 1994, 464 and T 211/90). In T 985/91 the board took the view, with reference to T 17/91, that late-filed documents should only be admitted into the proceedings under certain circumstances if they related to alleged prior use.
In T 17/91 an allegation of prior use based on the opponents' own activities had been filed two years after the expiry of the opposition period, with no good reason for the delay. This, in the board's view, constituted an abuse of the proceedings and a breach of the principle of good faith. Irrespective of its potential relevance, the allegation was therefore to be disregarded under Art. 114(2) EPC 1973.
Taking a similar line, the board ruled in T 534/89 (OJ 1994, 464) that an objection based on prior use by the opponents themselves which was raised only after the expiry of the opposition period, although the factual circumstances were known to the opponents, constituted an abuse of procedure.
In T 691/12 the board observed that a prior-use allegation first submitted in the appeal proceedings could not be admitted and considered as prior art unless it met at least the following three conditions: (a) it did not involve an evident abuse of procedure; (b) the prior use as alleged had prima facie to be so relevant that it cast doubt on the validity of the patent; and (c) the prior use had to be fully proven, requiring no further investigation to establish its nature or context. In the case in point these conditions were not met (see also T 1847/12, T 63/13).
In T 2393/13 the board decided to disregard an unsubstantiated allegation of prior use. Under Art. 12(4) RPBA 2007, facts and evidence not only had to be submitted at the appropriate time; they also had to meet the requirements in Art. 12(2) RPBA 2007, i.e. they had to be complete. See also T 380/00 (inadequately substantiated assertion of a non-confidential disclosure in a job interview).
In T 481/99 the board said that the principle that late-filed facts, evidence and related arguments should only exceptionally be admitted into the proceedings by the opposition division (see e.g. G 9/91, OJ 1993, 408 and T 1002/92, OJ 1995, 605) did not imply that a late-filed allegation of prior use, which would be relevant if proven, was to be automatically disregarded on the ground that the new facts first needed to be established by taking evidence. However, if the submissions and/or documents relating to the late allegation of prior use showed inconsistencies or even contradictions, the deciding body was entitled to disregard the alleged prior use pursuant to Art. 114(2) EPC 1973 without further enquiries.
On the issue of documents relating to prior use submitted during appeal proceedings, the board in T 508/00 ruled that poor communications within a company or a group of subsidiary companies did not constitute adequate and acceptable grounds for allowing the late submission of evidence concerning alleged prior use (see also T 443/09).
The board in T 1914/08 similarly refused to accept financial difficulties a party claimed to have experienced in the intervening period as justification for the late filing of previously announced – and so available – documents.
In T 450/13 the board stated that not substantiating a public prior use in opposition proceedings but attempting to substantiate it in the statement of grounds of appeal could lead to the inadmissibility of such a line of attack under Art. 12(4) RPBA 2007.
Likewise in T 444/09, T 12/11, T 1835/11, T 1295/12, T 1841/14 and T 2361/15 no account was taken of a public prior use alleged for the first time in appeal proceedings.