A document considered during the examination procedure is not automatically scrutinised in opposition or opposition appeal proceedings, even if it is quoted and acknowledged in the contested European patent (T 155/87, T 198/88, OJ 1991, 254; T 484/89, T 652/99). According to T 291/89 this also applied to a document cited in the search report. In T 111/04 the board agreed with the case law and considered that this applied also to evidence filed during the grant proceedings.
In T 536/88 (OJ 1992, 638) the board pointed out, however, that the document cited and acknowledged in the description of the contested patent itself as the closest prior art and on the basis of which the technical problem in the description was formulated remains an exception. Such a document also forms part of the opposition or opposition appeal proceedings even if it is not expressly cited within the opposition period (T 541/98, T 652/99, T 454/02, T 86/03).
In T 140/00 although document (7) had been cited in the specification of the patent in suit, it had merely been acknowledged as conventional background art; it was not considered therein as essential or as the closest prior art and starting point of the claimed invention. Therefore, that document did not automatically form part of the appeal proceedings and, thus, was late-filed evidence subject to a discretionary decision of the board.
In T 234/90, T 300/90 and T 501/94 (OJ 1997, 193) the board held that a document indicated in a citation as the closest prior art for the purpose of elucidating the technical problem set out in the citation did not automatically form part of the opposition or opposition appeal proceedings if not expressly cited within the opposition period.
Regarding this issue, the board commented in T 387/89 (OJ 1992, 583) on the scope of the principle of ex officio examination under Art. 114(1) EPC 1973 in opposition proceedings. In the board's view, neither an opposition division nor a board of appeal had any duty to reconsider the relevance of documents cited in the European search report if such documents had not been relied upon by the opponents to support their grounds of opposition. Under Art. 114(1) EPC 1973, however, an opposition division or appeal board could introduce new documents into the opposition proceedings if it had good reason to suppose that the documents could affect the outcome of the decision (T 420/93, T 530/00). In T 588/89 the board similarly introduced a document into the appeal proceedings under Art. 114(1) EPC 1973, because, in its view, the document reflected the closest prior art and raised doubts as to whether an inventive step had taken place.
In T 219/92 a document cited in the search report had to be taken into consideration in view of its relevance. The board also considered it justifiable to exercise its discretion under Art. 111(1) EPC 1973 to decide the case having regard to this document, since the responsibility for the late citing lay with the respondents and the decision was not to the appellant's disadvantage.