T 1991/23 - (II) When a witness must be heard on request of the other party

Key points

• The OD decided that an alleged public prior use exhibited all features of claim 1. The proprietor appeals. 
• "The appellant alleged a violation of the right to be heard, inter alia, due to the failure to comply with a request for evidence submitted by it "
•  
• The relevant section of paragraph 23.2 of the contested decision reads as follows: "The patent proprietor further requested that Mr. Grzegorz GALEZOWSKI and Ms. Sylvia BUCHER be heard as witnesses regarding the public prior use. The notice of summons stated that the Opposition Division did not intend to hear the witnesses nominated by the patent proprietor, since the burden of proof lies with the opponent and it is the responsibility of the opponent, not the patent proprietor, to select, present, and request appropriate evidence. If the Division concludes that the allegations are sufficiently proven, the patent proprietor could submit counter-evidence and request the hearing of rebuttal witnesses. The patent proprietor subsequently did not request the hearing of rebuttal witnesses.""" 
• "In this context, attention is drawn to the relevant passage on pages 4 and 5 of the appellant’s statement of defence dated 18 September 2019, which reads as follows:

  "The patent proprietor therefore requests - only conditionally, namely in the event that the opposition division finds that the alleged prior use is relevant (see below) - for legal certainty under Art. 117 and R. 117 EPC and for reasons of procedural economy, the hearing of actual witnesses on the facts of the case, namely: Mr Grzegorz GALEZOWSKI (author of the email in Annex A3) to the address in Annex A3" [....]

• " The condition that the opposition division finds the prior use relevant (OV1) has been met, and the opposition division does not provide sufficient reasons in its decision for not summoning the witnesses offered by the patent proprietor. The reference to the notice of summons, in which the opposition division stated that it did not intend to hear the witnesses nominated by the patent proprietor, since the burden of proof lies with the opponent and it is the responsibility of the opponent, not the patent proprietor, to select, submit, and request appropriate evidence, cannot justify this. "

• " First of all, it is incorrect that a party to the proceedings should generally be excluded from submitting evidence on factual issues for which another party bears the burden of proof. The (substantive) burden of proof determines to whose disadvantage the inability to clarify a factual situation affects. However, this does not mean that only the party to the proceedings with the burden of proof may contribute evidence to clarify this matter. Irrespective of this, the opposition division ultimately considered the disputed prior use to be proven, which is why its statement in the summons that the patent proprietor could present counter-evidence in this case became relevant."" 

• " The Board considers that the Opposition Division's statement that "the patent proprietor subsequently did not request the hearing of rebuttal witnesses" is incorrect. The appellant requested that Mr. Grzegorz Galezowski and Ms. Sylvia Bucher be summoned as witnesses. This request was not withdrawn by the appellant and did not need to be repeated."

• " In the Board’s view, the Opposition Division’s approach constitutes a violation of the right to be heard within the meaning of Article 113(1) EPC and thus constitutes a substantial procedural violation."

EPO 

The link to the decision can be found after the jump.

https://www.epo.org/de/boards-of-appeal/decisions/t231991du1