Fresh grounds for opposition submitted in appeal proceedings may be considered only with the approval of the patentee (G 10/91
, OJ 1993, 420). In T 1002/92
(OJ 1995, 605), however, the board focused on the issue of the late submission of facts and evidence to substantiate the original grounds for opposition cited in the proceedings before the opposition division. In interpreting Art. 114(2) EPC 1973
(unchanged), the board applied the principles laid down in G 10/91
and held that late-filed facts, evidence and related arguments should only exceptionally be admitted into the proceedings if, prima facie, there were clear reasons to suspect that such late-filed material would prejudice the maintenance of the European patent.