In T 951/92 (OJ 1996, 53) the board held that if a communication under R. 51(3) EPC 1973 and pursuant to Art. 96(2) EPC 1973 did not set out the essential legal and factual reasoning to support a finding that a requirement of the EPC had not been met, then a decision based on such a finding could not be issued without contravening Art. 113(1) EPC 1973, unless and until a communication had been issued which did contain the essential reasoning. If a decision was issued in the absence of a communication containing essential reasoning, Art. 96(2) EPC 1973 was also contravened, since in order to avoid contravening Art. 113(1) EPC 1973 it was "necessary" to issue a further communication (see also T 520/94, T 750/94, OJ 1998, 32; T 487/93, T 121/95, T 677/97).
In T 951/92 (OJ 1996, 53) the board summed up the case law by stating that Art. 113(1) EPC 1973 was intended to ensure that, before a decision refusing an application for non-compliance with a requirement of the Convention was issued, the applicant had been clearly informed by the EPO of the essential legal and factual reasons on which the finding of non-compliance was based. This was so that in advance of the decision he knew both that the application might be refused and why, and also so that he might have a proper opportunity to comment upon the reasons and/or to propose amendments so as to avoid refusal of the application. Thus the term "grounds or evidence" in Art. 113(1) EPC 1973 should not be narrowly interpreted. In particular, in the context of the examination procedure the word "grounds" did not refer merely to a ground of objection to the application in the narrow sense of a requirement of the Convention which was considered not to be met. The word "grounds" should rather be interpreted as referring to the essential reasoning, both legal and factual, which led to refusal of the application (T 187/95). In other words, before a decision was issued an applicant had to be informed of the requirement which he had to meet and had to have an opportunity of meeting it (see also T 520/94, T 750/94, OJ 1998, 32; T 487/93 and T 121/95).
In T 907/91 the examining division refused the application without informing the applicant of its grounds for not accepting the amended documents submitted after receipt of the first communication and after oral proceedings. The board held this action to be in breach of Art. 113(1) EPC 1973 because, prior to issuing the contested decision in written or oral proceedings, the examining division should have given its reasons for refusing to accept the amended documents. Such grounds could be of a formal nature or relate to substantive patent law, depending on the relevant provisions. However, other grounds could also be brought to bear, based on generally recognised principles of procedural law (see Art. 125 EPC 1973), such as the applicant's attempt to delay proceedings by submitting an excessively large number of requests for amendments in clear abuse of the patent grant procedure.
In T 763/04 the board stated that Art. 113(1) EPC enshrines a party's right to be heard before a decision is issued against it. In accordance with the established jurisprudence of the boards of appeal (see J 7/82, OJ 1982, 391 and T 94/84, OJ 1986, 337) this right also guarantees the right to have the relevant grounds fully taken into account in the written decision. The board held that Art. 113(1) EPC 1973 will be contravened where, as in the case before it, facts and arguments, which from the appellant's submissions are clearly central to his case and which may speak against the decision taken, are completely disregarded in the decision in question. The board stated that Art. 113(1) EPC 1973 requires not merely that a party be given the opportunity to voice comments, but more importantly that the deciding instance demonstrably hears and considers these comments. In summary, the right to be heard in accordance with Art. 113(1) EPC 1973 is contravened if the decision of the first instance fails to mention and to take into consideration important facts and arguments which may speak against the decision in question (see also T 206/10; T 246/08).