R. 116(1) EPC (R. 71a(1) EPC 1973) stipulates, inter alia, that, when the EPO issues the summons to oral proceedings, a final date for making written submissions in preparation for the oral proceedings must be fixed. New facts and evidence submitted after this date need not be considered, unless admitted on the grounds that the subject of the proceedings has changed. The same is true for applicants or patentees invited under R. 116(2) EPC (R. 71a(2) EPC 1973) to submit documents which meet the requirements of the EPC.
As construed according to its object and purpose, R. 116 EPC (R. 71a EPC 1973) is intended to give the decision-making department and other procedural parties enough time to prepare thoroughly for the oral proceedings and so ensure that they are not faced with surprising new facts and do not take potentially inappropriate decisions in undue haste (T 765/06; as to the reasons for the introduction of R. 71a EPC see T 343/08). The purpose of R. 71a EPC 1973 is to provide the EPO with a case management framework for the preparation of oral proceedings (T 798/05).
In T 452/96 the board emphasised that fixing a time limit under R. 71a EPC 1973 was not to be taken as an invitation to submit further evidence (see also T 39/93, OJ 1997, 134, and T 885/93) and therefore had no impact on the EPO's power to disregard late-filed documents (see also T 476/96). There is no general duty for an examining division to provide feedback on an applicant's reply to a summons to oral proceedings, in advance of such oral proceedings (T 343/08, see also T 462/06). In the ex parte proceedings T 462/06 the board also stated that the requirement of R. 116 EPC does not mean that already in the communication all lines of arguments or a detailed reasoning for the decision should be set out.
R. 116 EPC (R. 71a EPC 1973), and Art. 114(2) EPC on which it is based, refer to late-filed facts and evidence but not to new arguments, which can be made at any stage in the proceedings (T 131/01, OJ 2003,115; T 926/07, see also T 624/04). However, in the light of Art. 13 RPBA this may be different in appeal proceedings, see T 1621/09 where the board held that a new argument brought forward in appeal proceedings by a party which would have the effect of amending its case, even if the argument was based on evidence and facts already in the proceedings, can only be introduced into the proceedings at the discretion of the board by way of an amendment under Art. 13 RPBA.
For a comprehensive overview of the case law regarding late submissions in general (independent of the preparation of oral proceedings governed by R. 116 EPC), see Chapter IV.C.1, "Late submission". As to the applicability of R. 116 EPC (R. 71a EPC 1973) to the boards of appeal, see in this chapter III.C.4.4.2. For case law when the applicant files amended claims in appeal proceedings after the oral proceedings have been arranged and then does not attend them, see Chapter IV.E.4.2.6 d) "Applicant (proprietor) absent from oral proceedings".