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Date Published

Where a request to correct a clerical error or obvious mistake does not contravene the provisions of sec 102, evidence is not required. However, supporting evidence will usually be required where the requested amendments are for the purpose of correcting a clerical error or obvious mistake and would otherwise not be allowable under the provisions of sec 102.

Generally, in order to establish the existence of a clerical error, evidence in the form of a declaration that fully explains the facts surrounding the clerical error and the amendment sought will be required.  The level of evidence necessary to prove that a clerical error has occurred is specific to each case.  Where the examiner has doubts regarding the nature of the evidence provided then they should consult Patent Oppositions (OEP). 

Where the amendment relates to the correction of an obvious mistake, evidence may be required to establish that the instructed reader of the specification would consider the mistake and the correction as satisfying the requirements of an obvious mistake.

Amended Reasons

Amended Reason Date Amended

Clarified practice relating to the level of evidence required during the assessment of amendments relating to a clerical error or obvious mistake in response to improvement log item IIP-62.

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