4. Re-establishment of rights
A proprietor of a European patent or of a Unitary Patent who, despite taking all due care required by the circumstances, was unable to observe a time limit vis-à-vis the EPO may request the re-establishment of their rights. A "time limit" is taken to mean a specific period within which an act vis-à-vis the EPO must be completed (see EPC Guidelines, E-VIII, 1.1).