According to established case law, a computer-generated slideshow presentation is in essence the presentation of written material (T 1122/01; T 1110/03, OJ 2005, 302; T 1556/06; T 601/06). It is also established case law that the principles relating to the use of visual aids such as flip charts should also be applied to PowerPoint presentations. Therefore, a party wishing to use such a presentation should announce this intention early enough before the oral proceedings and should send both the board and the other parties a copy. Any objections could then be raised and considered at the oral proceedings before the presentation was given, and a decision could be made if need be (T 1122/01, T 1110/03, T 555/06, T 608/08).

In T 1122/01 the board pointed out that a PowerPoint presentation could be a way of introducing new means of evidence, or it could lead to a completely new and unexpected presentation of the case by a party. There was therefore a risk of the other parties being caught unawares by this, of new procedural issues being raised, and of the oral proceedings becoming protracted. See also T 1110/03, T 555/06.

In T 373/05, a few days prior to oral proceedings before the board the appellant (patent proprietor) asked for a screen for showing PowerPoint slides at the hearing, without however saying what the slides were about. At the start of the oral proceedings, it distributed paper versions of the slides, setting out arguments about the admissibility of the respondent's opposition and regarding sufficiency of disclosure. The board took the view that since they contained no new facts, their late submission was no reason to disregard them under Art. 114(2) EPC 1973. On the contrary, it felt that presenting the appellant's arguments visually on paper had also helped the respondents to prepare their responses. See also T 1528/12.

In the board's view in T 1556/06, the opposition division has discretion as to the way oral proceedings were conducted. It was not a wrongful exercise of this discretion, and thus not a procedural violation, to refuse to allow a party to use a PowerPoint presentation during oral proceedings if the party was not thereby prevented from presenting its arguments orally. See also T 608/08.