2.1 Introduction 

An applicant can request authorisation to rectify obvious mistakes in the international application. Rectification is authorised on condition that:

(i)the mistake is obvious to the skilled person, i.e. that something else was intended than what appears in the document concerned, and 

(ii)the rectification is obvious to the skilled person, i.e. that nothing else could have been intended than the proposed correction.  

The applicant may submit a request for rectification of an obvious mistake in the description, claims and drawings (not the abstract) of the international application (including amended documents) to the ISA or the IPEA, which is the competent body authority to authorise or refuse such rectification. If the obvious mistake is related to the request form (PCT/RO/101), it is the RO which authorises or refuses the rectification.

In cases where the EPO is not the competent authority with respect to the request for rectification but still needs to issue a PCT action, rectified sheets may already have been allowed by the competent authority concerned and the file will then contain these rectified sheets in addition to the originally filed documents.

Although the competent authority should not allow newly filed sheets that contain added subject-matter, it may happen that such rectified sheets do in fact contain amendments which go beyond the disclosure as originally filed. In such cases, this will be mentioned in the written opinion and/or report and, if necessary, the search and examination will be restricted to what was originally disclosed. However, the examiner is not required to systematically check such sheets for added subject-matter.

The language requirements for a request for rectification of an obvious mistake in the description, claims and drawings by the EPO as ISA or IPEA are set out in A‑VII, 3.1.