WARNING: Although the information which follows was correct at the time of original publication in the PCT Newsletter, some information may no longer be applicable; for example, amendments may have been made to the PCT Regulations and Administrative Instructions, as well as to PCT Forms, since the PCT Newsletter concerned was published; changes to certain fees and references to certain publications may no longer be valid. Wherever there is a reference to a PCT Rule, please check carefully whether the Rule in force at the date of publication of the advice has since been amended.
Q: I am about to file an international application; however, having just missed the 12-month priority period, I intend to request the restoration of the right of priority under PCT Rule 26bis.3. Since I have the possibility of filing the application with the United Kingdom Intellectual Property Office (an operating name of the Patent Office) (RO/GB), the European Patent Office (RO/EP), or the International Bureau (RO/IB) as receiving Office, and PCT Rule 26bis.3 applies in respect of each of those Offices, what factors should I take into account in deciding where to file the application and the accompanying request for restoration of the right of priority?
A: Essentially, you need to consider whether the Offices before which you are considering entering the national phase will recognize a restoration of the right of priority which is made by the receiving Office (RO) with which you intend to file your international application, and whether it will be easier to pursue the matter before the RO, or upon national phase entry before the designated Office (DO).
Most fundamentally, a significant number of DOs do not recognize restoration of the right of priority at all, or else not in the form envisaged by the PCT. A list of Offices which have made notifications under Rule 49ter.1(g) of the incompatibility of the relevant rules with their national law can be found at:
If all the Offices before which you are interested in entering the national phase are on this list, there is probably no point in seeking restoration of the right of priority at all. You will need to consider carefully whether your application is likely to be valid without the priority claim, or else whether there are any other specific national provisions which could save it in the Offices where you are interested in obtaining protection.
Where at least one of the Offices allows for recognizing the restoration of the right of priority in principle, it is desirable to seek the easiest process which is likely to be recognized without further actions being required in the national phase. The main consideration comes from the fact that the PCT leaves it to individual Offices to determine which of two criteria should be used in deciding whether to approve the restoration. This applies both in terms of their actions as an RO and (subject to the possibility of having alternative, easier, criteria) in terms of their actions as a DO. Whether the DO will recognize the restoration will generally depend on whether the RO made its decision based on a sufficiently stringent basis. If not, then further individual requests for restoration may be needed in some of the national phases.
All ROs in respect of which PCT Rule 26bis.3 is applicable (all except 17 ROs) must apply at least one of the following criteria when deciding on a request by an applicant for the restoration of the right of priority:
- failure to file the application within the priority period occurred in spite of due care required by the circumstances having been taken;
- failure to file the application within the priority period was unintentional.
In the case of your choice of ROs, the RO/GB has notified that it will apply only the “unintentional” criterion, the RO/EP has notified that it will apply only the “due care” criterion and the RO/IB will apply both criteria. It is recalled that a table entitled “Restoration of the right of priority by receiving Offices (RO) and designated Offices (DO) under PCT Rules 26bis.3 and 49ter.2” showing, where applicable, the criteria applied by the various ROs and DOs under the PCT, is available on the PCT Resources page at:
An RO may, if it wishes, apply both criteria for restoration and leave the choice to the applicant as to which criterion is sought to be applied in a specific case. Provided that it is prepared to apply both criteria, an RO is free to apply, upon request by the applicant or at its own initiative, first the “due care” criterion and then, if it finds that that criterion is not satisfied, the “unintentionality” criterion. This is what is done by the RO/IB.
Meeting the due care criterion, which is applied by both the RO/EP and RO/IB will give the most widely effective result as it is stricter than the unintentionality criterion, and the decision by an RO to restore the right of priority based on due care will, as a general rule1, be effective in all DOs (PCT Rule 49ter.1(a)) except those which have submitted a notification of incompatibility under PCT Rule 49ter.1(g). Thus, it is in the applicant’s interest to, if at all possible, meet this criterion.
The unintentionality criterion is much less strict, and if the RO does restore a right of priority based on that criterion, that decision will be effective only in those designated States whose applicable national laws provide for restoration of the right of priority based on that criterion, or on a criterion which, from the viewpoint of applicants, is more favorable than that criterion (PCT Rule 49ter.1(b)). On the other hand, if you are sure that all of the DOs before which you are interested in entering the national phase fall into that category, it may be easier, and in some cases cheaper, to demonstrate that you have met that criterion.
If you wish to file your international application with an Office which applies the due care criterion, it is important to consider the circumstances behind your failure to file the application within the priority period, and the likelihood of successfully meeting that criterion in the particular circumstances of that case. When requesting the restoration of the right of priority, you should state the reasons for the failure to file the international application in time, providing a summary of the facts or circumstances surrounding the failure to file the international application in time, including, where applicable, actions that were taken to prepare and file the international application. The RO may require that the statement of reasons be substantiated by a declaration or evidence which would enable it to determine whether the failure to file the international application within the priority period occurred in spite of due care, that is, if all reasonable care was taken under the circumstances to ensure that the priority period would not be missed (see the PCT Receiving Office Guidelines, paragraphs 166F and 166G).
Individual cases will be examined on a case by case basis. If the RO concerned only applies the due care criterion, which is the case of the RO/EP, and if you cannot provide convincing evidence that the failure to file the application within the priority period occurred in spite of due care required by the circumstances having been taken, your priority claim will not be restored at all at this stage. Note, however, that even if you do file your application and request restoration of the right of priority with the RO/EP and it finds that the due care criterion has not been met and does not restore the right of priority, that negative decision can always be reviewed by a DO, unless it has submitted a notification of incompatibility under PCT Rule 49ter.1(g).
If you do not believe that the RO will restore the priority claim based on due care, you could file your international application with the RO/GB, which is more likely to restore the right of priority under the criterion of unintentionality as, for this criterion, it should generally be sufficient to simply furnish a statement indicating that the failure to comply with the priority period was not intentional (if that is indeed the case) (see PCT Receiving Office Guidelines, paragraph 166G). Furthermore, if you file with the RO/IB, it will automatically review the application first under the due care criterion and then under the unintentional criterion.
You may also wish to consider the financial aspects of your choice of RO, and the amounts charged (if any) for the transmittal fee and for the fee for requesting a restoration of the right of priority before each Office – for the transmittal fee, the RO/EP currently charges 110 euro (EUR), the RO/GB charges 55 pounds sterling (GBP) and the RO/IB charges EUR 64; for the request for restoration of the right of priority, the RO/EP charges EUR 550, whereas the RO/GB and RO/IB do not charge any fee.
Applicants are always strongly advised to file well before the end of the 12-month priority period in order to avoid the problems caused by last-minute delays, and being in a position where restoration of the right of priority has to be requested, and might not be effective in all the Offices where protection is sought anyway.
For further information on the restoration of the right of priority, see the “Practical Advice” in PCT Newsletter Nos. 09/2009 and 04/2007, the PCT Applicant’s Guide, International Phase, paragraphs 98A to H, and the part of the “Frequently Asked Questions: Amendments to the PCT Regulations (April 1, 2007)” concerning the restoration of the right of priority at:
Additional information concerning the practical advice published in PCT Newsletter No. 10/2009
Reference is made to the above-mentioned “Practical Advice” entitled “Choosing a receiving Office as a function of the criterion applied by it for restoring the right of priority”. It was explained that, in the case of a request for restoration of the right of priority under the criterion of unintentionality, it should generally be sufficient to furnish a statement indicating that the failure to comply with the priority period was not intentional, as stated in the PCT Receiving Office Guidelines, paragraph 166G.
The main message of the practical advice was that "unintentionality" is an easier test to meet than "due care". It should be noted as well that, as stated in the first sentence of paragraph 166G, the receiving Office may require that a declaration or other evidence in support of the statement of reasons be furnished or, if some evidence has already been provided, that additional evidence be furnished. As an example, the United Kingdom Intellectual Property Office (an operating name of the Patent Office) (RO/GB), a receiving Office which applies only the “unintentionality” criterion, has notified the International Bureau that, in considering whether the unintentional criterion has been met, it takes the same approach as it does for equivalent requests under its national law, and requires reasons and evidence to be provided to allow it to determine why the priority period was not met, and thus to establish whether the failure was unintentional.
Applicants are advised to check with their respective Offices what kind of evidence, if any, is required in support of their requests for restoration of the right of priority.
Date retrieved: 17 May 2021