4.3. Standard of proof
See chapter III.S.4. "Spheres of risk and apportioning the burden of proof" and Administrative Council decision CA/D 6/14 dated 15 October 2014 (entry into force: 1 April 2015) amending R. 2 EPC, R. 124 EPC, R. 125 EPC, R. 126 EPC, R. 127 EPC, R. 129 EPC, R. 133 EPC and R. 134 EPC (OJ 2015, A17; explanatory notice: OJ 2015, A36), discussed in the chapter on notification (R. 126(1) EPC was further amended by Administrative Council decision CA/D 2/19). With respect to the burden of proving receipt, see also chapter III.G.5.1.2 f) below.
The respondent (opponent) in T 1/12 argued that the boards' case law on the applicable standard of proof for proving receipt of documents by the EPO was contradictory. In that context, it cited T 1200/01, which suggested a balance of probabilities, and T 2454/11, which held that a stricter standard of proof was needed to convince the board. This prompted the opponent to draft points of law for referral. The board, however, refused its request for a referral, in particular because according to the principle of free evaluation of the evidence, that evaluation had to done on a case-specific basis. The standard of proof that the balance of probabilities needed to reach to convince the board was thus left to the discretion of the board itself. The board found no clear contraction between T 1200/01 and T 2454/11. It dealt with the matter of the standard of proof in combination with, in particular, the principle established in the case law of free evaluation of the evidence.
The issue under appeal in T 1200/01 was whether an opposition of the appellant against the patent could be deemed to have been filed. According to Art. 99(1), last sentence, EPC, this was only the case if the opposition fee had been paid within the opposition period. However, in the case at issue no trace of a notice of opposition nor of a voucher for payment of the opposition fee allegedly filed by the appellant had been found within the EPO. The board noted that, concerning the standard of proof to be applied for establishing the receipt of documents not found within the EPO, it was the established case law of the boards of appeal that, even if proof to this effect could seldom lead to absolute certainty, it at least had to show to a high degree of probability that the alleged filing had taken place (see also T 128/87 date: 1988-06-03, OJ 1989, 406, cited by the board). It also noted that in some previous cases (see T 243/86 and T 69/86, cited by the board) it had been accepted that this standard was met if there were concrete traces of the item sought which, even if they did not show it for certain, indicated a high probability of the lost document having once been in the EPO. Nevertheless, any other means of giving evidence, such as witness testimony, could equally be considered in this context.
The communication noting the loss of rights under R. 112(1) EPC (former R. 69(1) EPC 1973) is deemed to have been delivered to the addressee on the tenth day following its posting, unless the letter failed to reach the addressee or reached him at a later date. In the event of any dispute, it is incumbent on the EPO to establish that the letter reached its destination (R. 126(2) EPC; CA/D 6/14 for the revised wording; former R. 78(2) EPC 1973). In J 9/05 and J 18/05, the only evidence provided by the examining division was a letter from the Deutsche Post referring to the information received from the foreign postal service, according to which the letter had been delivered to an authorised recipient, who, however, was not specified. The board stated that the probative value of the submissions and evidence of the appellant had to be balanced against the probative value of evidence established by the EPO. Balancing the evidence of the examining division, which consisted of the rather vague letter from the Deutsche Post, against the evidence submitted by the appellant, and taking into account the serious consequences for the appellant, the board came to the conclusion that it had not been sufficiently proven that the applicant had received the R. 69(1) EPC communication. In such a situation, where the EPO bore the burden of proof, the applicant had to be given the benefit of the doubt.
In T 529/09 a communication pursuant to R. 82(3) EPC (invitation to parties to file observations with regard to the maintenance of patent in amended form) had been sent out on 8 September 2008 by registered letter addressed to the proprietor's representative. According to R. 126(2) EPC (see CA/D 6/14 for the revised wording) a registered letter was deemed to have been delivered to the addressee on the tenth day following its posting, unless it had failed to reach the addressee or reached him at a later date. In the board's view, "delivered to the addressee" did not mean that the notification in question had to be brought to the attention of the professional representative in person. It sufficed that the registered letter had been received by a person authorised to take delivery, e.g. an employee of the representative's office (see T 743/05). In the present case, the board regarded the evidence on file as sufficiently reliable and complete to prove the proper delivery of the letter. In this respect, the board highlighted a significant difference between this case and J 9/05 and J 18/05, in which the appellant had filed a considerable amount of counter-evidence pointing out specific reasons why the letter might not have been received by the representative's office.
In T 1934/16, since the appellant denied having received the communication under R. 82(3) EPC, the EPO had to establish that it reached its destination and the date on which it was delivered (R. 126(2) EPC). The result of the enquiry initiated by the board proved that the registered letter reached its destination and, as the appellant did not submit substantiated details that were apt to demonstrate a different course of events, no doubt existed that the letter was duly received by the appellant's representative.
The inter partes decision T 1587/17 deals in detail with the standard of proof required to establish that a notice of appeal has been filed, with particular reference to T 2454/11 and T 1200/01. The board decided that, in view of the evidence on file, the appellant had discharged its burden of proof and the respondent had not succeeded in raising doubts that were serious enough.
See also J 10/04, reported above, which differed from the "ordinary" cases concerning lost mail in that the application had reached the USPTO and only some of the papers were missing, and T 1535/10, in which the board found that responsibility for obstacles and delays in receiving decisions having to be notified under R. 126(1) EPC had to be assigned according to spheres of risk (see chapter III.S.4. "Spheres of risk and apportioning the burden of proof").