If the filing date of the PCT application is within 2 months from the deadline and if the applicant files a request for restoration of priority with the JPO, the JPO may accept the priority. In order to be accepted by the JPO, there must be a legitimate reason that the JPO will accept.

If the receiving office restores the priority based on PCT rule 26bis3 and if the reason for restoration was that a failure occurred in spite of due care required by the circumstances, then, for PCT applications filed on or after April 1, 2015, the restoration will be accepted by the JPO.

If the reason for restoration was unintentional, it will be necessary to file a request for restoration of priority in the JPO.

If the receiving office restores the priority based on PCT rule 49ter1 and if the reason for restoration was that a failure occurred in spite of due care required by the circumstances, the JPO will accept the restoration of priority, and it will not be necessary to file any documents with the JPO.

However, if the receiving office restores the priority on the basis that the reason for restoration was unintentional, the restoration at the international stage will not be automatically accepted by the JPO. The applicant must file a request for restoration of priority with the JPO. If such a request is not filed with the JPO, the JPO will not examine whether or not the restoration at the international stage should be accepted.

Within one month* after the deadline for entering the Japanese national phase (for applications filed in English, the deadline for filing a Japanese translation of the PCT application), the applicant must file a Notice of Reasons for Restoration including legitimate reasons as to why the applicant was not able to claim priority by the deadline. Further, evidential documents to prove that the reasons are legitimate must be submitted with the notice.

*If a request for examination is filed within the national phase entry deadline, within one
month from the date of filing the request.