R. 75 EPC explicitly states that an opposition may be filed even if the opposed patent has been surrendered or has lapsed in all the designated Contracting States. With respect to appeals in opposition proceedings, a similar provision is contained in R. 98 EPC.
In T 606/10 the opposed patent had already lapsed before the opposition against it was filed. The opposition division had maintained the patent in amended form. Both the opponent and the patentee appealed.
The board referred to R. 78 and 98 EPC. It was the board's understanding that R. 84(1) EPC did not apply to the situations falling under the separate legal provisions of R. 75 and 98 EPC. In those situations, the opponent when filing the opposition or the appeal would normally be very well aware that the patent had already lapsed so that the notice of opposition or appeal would clearly show his interest in the revocation of the patent with retroactive effect (see Art. 68 EPC). Thus, it was difficult to see any need for the mechanism provided in R. 84(1) EPC, according to which the EPO had to inform the opponent of the lapse of the patent and the proceedings could be continued only after the filing of a corresponding request by the opponent.