Re-establishment of rights constitutes a legal remedy for curing a loss of rights in proceedings before the EPO. If the requirements of Art. 122 EPC and R. 136 EPC are fulfilled and the request for re-establishment is granted, the requester will be treated as if the loss of rights had not occurred (see Art. 122(3) EPC). After the revision of the EPC, further processing has become the standard legal remedy for missed time limits in the European patent grant procedure (see also Chapter III.D.2 "Further processing under Article 121 EPC") and thus in some cases has replaced re-establishment (for a synopsis of the changes see "Case Law of the Boards of appeal of the EPO", 6th edition 2010, Chapter VI.E.1, and OJ SE 4/2007).
The main requirements for a re-establishment of rights are that the requester had the right to file the request (point 1. below), he was unable to observe a time limit within the meaning of Art. 122(1) EPC (which is not excluded under Art. 122(4) and R. 136(3) EPC) and this failure had the direct consequence of causing a loss of rights (point 2. below), the request was filed in time and in due form and the omitted act was made good within the time limit (point 3. below), and the substantive conditions were met, in particular all due care required by the circumstances had been taken (point 4. below).