5.1 Continuation in the case of surrender or lapse of the patent 

If the European patent has been surrendered or has lapsed for all the designated states, the opposition proceedings must be continued at the request of the opponent filed within two months after the date on which the opposition division informed the opponent of the surrender or lapse. Evidence of the lapse must generally be provided by submitting extracts from the Patent Registers of the designated contracting states.

Surrender or lapse has immediate nonretroactive effect (i.e. patent protection ceases on the date of surrender or lapse), whereas a revoked patent is deemed to have had no effect from the outset (Art. 68 EPC). So the opponent may still have an interest in the revocation of a lapsed or surrendered patent.

If, in the case of a request for continuation of the proceedings, the patent proprietor has renounced before the competent authorities in the designated states all rights conferred by the patent with ab initio and universal effect, or if no request for continuation has been received within the time limit, the opposition proceedings will be closed. The decision to close the proceedings will be communicated to the parties.

A statement by the patent proprietors making it unambiguously clear that they no longer wish their patent to be maintained is considered to be a request for its revocation, irrespective of the wording used (T 237/86). For details of the procedure to be followed, see D‑VIII, 1.2.5.