The stay of proceedings is a preliminary procedural measure sui generis which is justified as a preventive measure to preserve the third party's possible rights to the patent in dispute and which takes immediate effect (J 28/94, J 15/06). In particular, the stay of the grant proceedings is ordered by a communication of the EPO without having heard the applicant. However, the applicant may, in view of the said communication, request the issuance of an appealable decision.

Stay of proceedings implies that the legal status quo existing at the time of the suspension is maintained, i.e. neither the EPO nor the parties can validly perform any legal acts while proceedings are suspended (J 38/92). In particular, the applicant is not allowed to withdraw either the European patent application or the designation of any contracting state (Rule 15). Likewise, no divisional application can be filed during the stay of proceedings (J 20/05 and J 9/12).

An automatic debit order ceases to be effective on the day on which a stay of the proceedings under Rule 14 takes effect (see Point 13.1(e) AAD, Annex A.1 to the ADA, Supplementary publication 5, OJ EPO 2017). Therefore, after resumption of proceedings a new automatic debit order is needed, if the applicant wishes to continue using the automatic debiting procedure.