6.1.17 Rule 91 Obvious Mistakes in Documents

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Introduction

Rule 91.1 provides that obvious mistakes may be rectified. If a rectification is not of this nature (for example, if it involves cancellation of claims, omission of passages in the description or omission of certain drawings), it should be treated as an amendment under Articles 19 or 34 and dealt with on that basis (see also 6.3.9.1 Article 19 or Article 34(2)(b) Amendments).

Obvious Mistake

Mistakes which are due to the fact that something other than what was obviously intended included in the contents of the international application may usually be rectified. The mistake must be ‘obvious’ in the sense that it is immediately apparent:

  • that a mistake has occurred

  • that anyone would immediately recognise that nothing else could have been intended other than the rectification requested by the applicant

Examples of obvious mistakes that are rectifiable — as long as the meaning of the disclosure does not change upon entry of the rectification — include:

  • linguistic mistakes

  • spelling mistakes

  • grammatical mistakes

Mistakes in chemical or mathematical formulae are generally not rectifiable unless the correct formulae would be common knowledge to anyone.

Processing requests under Rule 91

Where a request for rectification in respect of any document (other than the Request form) is submitted to the International Searching Authority, PCT Unit will action the request for rectification in ePCT. Once processed the request will appear in RIO and the PCT unit will then contact the relevant examiner to alert them of the request (see Rule 91.1Ad. Inst. 511 PCT/GL/ISPE/12 at Chapter 8).

Any request for rectification from the applicant will be in the form of a letter. However, the PCT Unit, acting as the Receiving Office (RO), can also forward replacement sheets to the search examiner for consideration under Rule 91. For example, this can occur where the applicant has supplied a replacement sheet for another reason (e.g. to correct a defect) and the PCT Unit believes that it contains additional matter.

The search examiner considers whether the mistake is rectifiable under Rule 91.1, and completes form PCT/ISA/217 (see Annex J).

Notes:

  • Rule 91.1(c) to (g) is the only source of instruction when considering requests for rectification, i.e. case law does not exist.

  • Although Rule 91.1(h) allows the International Search Authority (ISA) to invite rectifications (form PCT/ISA/216), it is not envisaged that such invitations will be issued.

    • This is because any error which can be rectified under Rule 91 will not cause any problems in establishing the search report.

  • Authorisation of rectifications is determined solely by Rule 91.3(a) and (b) while Rule 91.1(c) determines if they are of effect.

    • Whether such rectifications can be effective is not a consideration in authorizing and thus of no examiner concern (see Rule 91.1(c) to (g) and Rule 91.3(c)).

Amended Reasons

Amended Reason Date Amended

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