Article 91 Correction of errors in patents and applications

Except where rule 45(3) or paragraph 4 of Schedule 4 has effect, a request for the correction of an error of translation or transcription or of a clerical error or mistake in any specification of a patent, in an application for a patent or in any document filed in connection with a patent or such an application shall be made on Patents Form 11/77 clearly identifying the proposed correction; and the comptroller may, if he thinks fit, require that the correction be shown on a copy of the document of which correction is sought.

Where such a request relates to a specification, no correction shall be made therein unless the correction is obvious in the sense that it is immediately evident that nothing else would have been intended than what is offered as the correction.

Where the comptroller requires notice of the proposed correction to be advertised, he shall advertise the request and the nature of the proposed correction in the Journal.

At any time within two months after the date of the advertisement, any person may give notice to the comptroller of opposition to the request on Patents Form 15/77.

Such notice shall be accompanied by a copy thereof and be supported by a statement in duplicate setting out fully the facts on which the opponent relies and the relief which he seeks.

The comptroller shall send a copy of the notice and the statement to the person making the request who, if he desires to proceed with the request, shall within the period of two months beginning on the date when the copies are sent to him, file a counter-statement in duplicate setting out fully the grounds on which he contests the opposition and the comptroller shall send a copy of the counter-statement to the opponent.

The comptroller may give such directions as he may think fit with regard to the subsequent procedure.