4.5.3 Prima facie relevance
Regarding the examination of evidence, documents and other submissions as to their relevance, one line of case law holds that "irrelevant" means no more "weighty" or "cogent" than those already on file (see e.g. T 611/90, OJ 1993, 50, and also the decisions summarised below).
In T 560/89 (OJ 1992, 725) the board explained that Art. 114(2) EPC 1973 allowed the EPO to disregard documents which contained no more information than the documents filed on time and did not disclose matter which could change the outcome of the decision. In T 1557/05, the appellant (opponent) filed further patent documents as prior art. The board held that late-filed evidence was admissible only if it is prima facie more relevant than the evidence already on file. In this regard the board in T 1883/12 added that relevance was decided in relation to facts to be proven, and if late documents (here: patent documents), on the face of it, were not more relevant to those facts than admitted evidence and thus appeared to add nothing, it was perfectly reasonable in the interest of procedural economy not to admit them.
Similarly, the board in T 1690/15 rejected the appellant's argument that relevance had to be assessed absolutely. It pointed out that an opposition division carried out its prima facie assessment by comparing the features obvious from the disclosure at issue with the claimed subject-matter. If it concluded that those features did not provide it with any evidence beyond that already on file, it could justifiably disregard the disclosure. If it was clearly no better than the previously cited prior art, it could already be assumed that it was no more likely to result in a finding of a lack of patentability.
In another line of case law, however, the boards have held that, in establishing whether a document was prima facie relevant, the decisive factor is not whether it is even more relevant than a previously filed document, but rather whether it is prima facie relevant for the outcome of the case (see e.g. T 1652/08, T 66/14 and T 1348/16).The board in T 66/14 further explained that this could not be assessed in isolation from the submissions put forward by the party submitting a document late; in exercising its discretion, the opposition division had to consider what objection the late-filed document was supposed to substantiate.
In T 2165/10, documents E1-E10, which related to an alleged public prior use, had not been admitted into the proceedings by the opposition division. The board held that the prima facie relevance test had been exercised correctly. The opposition division had considered, with regard to novelty, that E1-E10 did not disclose a number of the claimed features and, with regard to inventive step, that they did not deal with the problem underlying the contested patent. Since there was a document (D4) that related to this problem, the board could not find fault in the division's reasoning that the prior use was less relevant as the starting point.