Missed The PCT Filing Deadline? Here's What To Do

Potter Clarkson


Potter Clarkson is one of Europe’s leading full-service IP law firms. Our IP attorneys and solicitors maximise the value of our clients' innovation by providing the experience, vision and clarity required to create, protect, leverage and defend their ideas in the most commercial and strategic ways all over the world.
A valid priority date is often crucial to the outcome of a patent application. Therefore, ensuring that a patent application is filed in due time within the 12-month priority period is vital.
UK Intellectual Property
To print this article, all you need is to be registered or login on Mondaq.com.

A valid priority date is often crucial to the outcome of a patent application. Therefore, ensuring that a patent application is filed in due time within the 12-month priority period is vital. For cases where the priority deadline is missed, this article summarises actions to try to recover the lost rights.

A priority deadline missed only by a narrow margin may be salvaged if the deadline fell on a non-working day, in which case the deadline will automatically roll over onto the next working day. Therefore, it is worth making an initial check to ascertain whether the deadline fell on a weekend or national holiday applicable to the relevant receiving office. Different receiving offices have different closure days and it is the closure status of the chosen competent receiving office that is relevant.

In some countries, if it is identified that the priority deadline passed the previous day then it may be possible to make use of time zone differences to use an office where it is still the day before. For example, the discovery of a docketing error resulting in a deadline passing on Monday discovered at 9:00 Tuesday, in Canberra, Australia could be addressed by having the PCT application filed at the USPTO by attorneys based in California, where it is still within the working day on Monday.

If the priority deadline has been missed by a more substantial amount of time, but not exceeding two-months, then the right to priority for a PCT application may be restored. There are two opportunities to request this: (1) at the international phase and/or (2) at individual designated offices when the application enters the national phase.


Formal requirements

A request for restoration in the international phase is submitted to and decided upon by the receiving office for the application. The patent application must be accorded a filing date by the receiving office which is no later than two months after the expiry of the priority period. The priority claim must also be made with or added to the international application within this time period.

The deadline for filing a request to restore the priority date and paying the fee for restoration is also two months from the date on which the priority period expired. Notably, the international application and the request for restoration need not be filed together at the same time. In fact, it is usually best to file the international application as soon as possible - to obtain the earliest possible filing date should the request to restore the priority date be denied - and take some extra time, if available, to prepare a complete request for restoration.

The request for restoration must include a statement of reasons for failing to meet the priority deadline and provide any relevant declarations or evidence to support the application.

If granted, a restoration at the international phase may be effective before certain designated offices when the application enters the national phases. However, some exceptions apply. For example, Brazil and Germany take a very harsh stance with regard to the priority deadline and will neither admit a request for restoration of the priority date at the international phase nor recognise a restoration as a designated state. Others, such as Canada and Mexico, take a slightly more lenient stance in that, even though as designated states they will not recognise a restored priority date, they may admit and decide upon requests for restoration at the international phase1.

Merit of the request for restoration

It is imperative to understand the criterion applied by a receiving office when they assess the merit of a restoration request. Some offices may allow restorations only if the deadline was missed despite all due care required by the circumstances having been taken. Others may assess the merit of the application based on whether the applicant can demonstrate that missing the deadline was unintentional. Some offices may apply both. These criteria and may be applied with varying standards depending on the office you are dealing with because of divergence in their national caselaw. WIPO maintains a useful list of the standard applied by various national offices acting as the receiving office or designated office.

In practice, the unintentional criterion is quite a low bar when compared with all due care, which is generally much more difficult to demonstrate successfully. Examples of offices which apply the unintentional criterion include UKIPO, USPTO, and Japan Patent Office. Importantly, the EPO applies the all due care criterion.

In cases where the applicant only wishes to enter the national phase in countries which recognise the unintentional criterion, choosing the unintentional criterion is a way of increasing your chances of a successful restoration and, generally speaking, save money on preparing the request for restoration. However, any restoration granted at the international stage on the basis of the unintentional criterion will not be effective before designated offices which apply the all due care criterion.

The choice of receiving office when filing a PCT application beyond the priority deadline is therefore an important consideration. Choosing the International Bureau as receiving office keeps your options open by allowing both criteria to be assessed, whereas filing at a specific national office may restrict you to their chosen criterion.


If the applicant intends to request restoration of the priority date at the national phases, it is still important to include the priority claim in the international application at the outset. No priority claim may be added beyond a maximum time limit of the later of 16 months from the priority date as filed or the priority date as corrected or four months from the international filing date.

Typically, the deadline for requesting restoration of the priority claim before a designated office is one month after national phase entry. However, depending on the circumstances, the deadline for filing a request for restoration at a national phase may fall on or shortly after entering the national phase. Therefore, it is important to organise preparation of the request well in advance of the 30/31 month deadline.

The criterion applied for assessing the merit of the request will depend on the national office.


Requesting restoration of priority date at the international phase provides the advantage of potentially saving costs, in that an international-phase restoration of the priority date may be effective before a number of designated offices when entering the national phase, and providing certainty as to the outcome of the request before deciding to enter the national phases. The latter point may be of particular value when one is aware of prior art that would become relevant if the priority date is invalid.

Generally, requesting restoration at individual national phases is disadvantageous if the applicant require restoration in lots of countries - coordinating multiple restoration requests which may increase costs significantly. Further, the decision on the restoration of priority date will not be delivered until the cost of entering the national phases have already been incurred. However, if an effective decision to restore priority cannot be obtained in the international phase then the ability to request restoration when entering the national phase could prove to be a valuable back up option.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

See More Popular Content From

Mondaq uses cookies on this website. By using our website you agree to our use of cookies as set out in our Privacy Policy.

Learn More