16 May 2022

European Patent Office proposes to abolish the ’10-day rule’

UPDATE as of 19 October 2023

The European Patent Office (EPO)’s ‘10-day rule’ will cease to exist from 1 November 2023. From that date, EPO communications will be deemed to be delivered on the same date which they show, rather than 10 days later (as occurs at present). Click here to find out more.


Users of the European patent system will be familiar with the European Patent Office’s (EPO) ’10-day rule’. This is a legal fiction under which official communications from the EPO are normally deemed to have been delivered to the recipient 10 days after the date which they bear. In many cases, it is the end of the 10-day period which is relevant for calculating deadlines, even if the communication was received before then. While not strictly accurate, some users are in the habit of regarding the 10 days as a ‘grace period’ for response to EPO communications.

Although this rule originated as a ‘buffer’ to take into account delays in receiving documents by post, it has continued to be applicable even as the EPO has increasingly moved towards electronic communication. However, this now looks set to change.

At a meeting held by the EPO Committee on patent law on Thursday 12 May 2022, a proposal for ‘dropping’ the 10-day notification rule was preliminarily approved. The proposal still needs to be approved at the Administrative Council meeting in June, but assuming it passes there too, we can expect this change to come into force on 1 February 2023. The proposed change will abolish the 10-day rule regardless of whether communications are delivered electronically or by post.

Essentially, this means that the EPO’s provisions on notification will be brought in line with the PCT, such that the date of a communication will be considered the date of notification and be decisive for determining the expiry of an applicable deadline. As a safeguard against late delivery of communications, the EPO has proposed measures to extend deadlines in cases where delivery of a document is disputed, and it can be established that a document was delivered to the addressee more than seven days after the date it bears. Here the burden will be on the EPO to establish when the document was actually delivered, unlike the PCT, which places the burden on the applicant to prove late receipt.

The proposal to abolish the 10-day rule is part of a wider strategy to support digital transformation in the patent grant procedure. The changes also acknowledge that today’s reality of rapid postal services and electronic communication is very different to the paper-based world that much of the EPC is based on.

Other proposed changes permit transmission of prior art citations to applicants online rather than on paper, acknowledging that such citations might not always be simple written documents but might also be in multimedia formats. The EPO also proposes to rewrite the rules relating to the format of patent application documents in order to relax many of the (now largely obsolete) requirements relating to paper size, quality and formatting, which were designed for documents filed in hard copy. Notably, amendments to the rules on drawings seem to suggest that the EPO might in future allow applicants to submit colour drawings, which would be a very welcome change for applicants in many technical fields. These changes (amongst others in the overall proposal) are proposed to come into force on 1 November 2022, earlier than the proposed notification changes. We will continue to provide updates as more developments at the EPO are made public.