In order to determine whether the request for rectification of obvious mistakes can be authorised, the examiner should check that the time limit for requesting rectification has not expired. The request for rectification can only be considered if it is filed with the competent authority within 26 months from the priority date.
If the request is too late, it is refused on that ground.
If the request is in time, the examiner must check whether the requested rectifications satisfy the above criteria (i) and (ii) (see GL/PCT‑EPO H‑IV, 2.1).
Authorised replacement pages or sheets for rectification of obvious mistakes under Rule 91 are deemed to be part of the international application "as originally filed". These sheets are identified with "RECTIFIED SHEET (RULE 91.1)".
Rule 91.1
GL/ISPE 17.16
PCT AI Section 607
If authorisation of a request for rectification is refused, the applicant may request the IB in writing, within two months of the refusal, to publish the refused request together with the reasons for refusal, subject to payment of a special fee.