In T 42/84 (OJ 1988, 251) the board held that the Guidelines were not legally binding and a failure by the examining division to follow them was not in itself a procedural violation within the meaning of R. 67 EPC 1973 unless it also constituted a violation of a rule or principle of procedure governed by an Article of the Convention or one of the Implementing Regulations (see also T 647/93, OJ 1995, 132; T 51/94; J 24/96 OJ 2001, 434; T 937/97).