Other than in cases in respect of which the EPC specifies a fixed period which may not be extended, the duration of time limits may be extended on request. The request must be submitted in writing before expiry of the period that has been set. The extended period is to be calculated from the start of the original period.[Rule 132; ]

In opposition proceedings, requests to extend time limits over and above the normal period of four months, both for communications from an opposition division raising matters of substance and communications issued by the formalities officer, or two months for communications requesting an act of a merely formal or minor character (E‑VIII, 1.2), will only be granted in exceptional, duly substantiated cases. For a communication under Art. 101(1) and Rule 79 or Rule 81(2) and Rule 81(3), all parties to the proceedings can request an extension irrespective of whether they were invited in the communication to reply: if the extension is, exceptionally, granted to one of the parties, it automatically applies to all other parties.

In other proceedings, a request for extension, even if filed without reasons, is normally allowed if it is for not more than two months and the total period set does not thereby exceed six months. A request for a longer extension, especially if the total period set exceeds six months, is allowed only exceptionally, when the reasons given are sufficient to show convincingly that a reply in the period previously set will not be possible. Such exceptional circumstances might be e.g. the fact that representatives or clients are so seriously ill that they cannot deal with the case in time; or the need to perform extensive biological experiments or tests. On the other hand, foreseeable or avoidable circumstances (e.g. leave, pressure of other work) are not accepted as a sufficiently exceptional circumstance (see Notice of the Vice-President of Directorate-General 2 of the EPO, OJ EPO 1989, 180).

If the request for an extension is granted, the parties are informed of the new time limit. Otherwise, they are told that the relevant sanction has taken effect or will take effect.

An application will be removed from the PACE programme (see E‑VIII, 4) if the applicant has requested an extension of a time limit (OJ EPO 2015, A93, point A.4).

In examination proceedings, failure to respond to a communication according to Art. 94(3) results in deemed withdrawal of the application (see E‑VIII, 1.8, and E‑VIII, 1.9.2).

If the request for extension of a time limit filed in good time has been rejected and any applicant considers this unjust, they can only overcome the ensuing loss of rights by requesting a decision under Rule 112(2) and/or further processing under Art. 121(1) and Rule 135(1) (see E‑VIII, 2), as applicable. Where the reimbursement of the fee for further processing is requested and this is rejected, such decision is open to appeal, either together with the final decision or separately, as the case may be (see J 37/89).[Art. 106(2); ]

The failure of a party to reply to a communication from the opposition division within the period set does not lead directly to any legal consequence. Rather, the opposition proceedings will proceed to the next stage, and this could be a decision under Art. 101(2) or Art. 101(3).