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Examination of an additional application cannot commence unless a request for examination of the parent has been made (sec 81(2)).  Where a request for examination of the parent has not been made, examiners should refer the parent application to COG for the issuance of a direction under sec 44(2).  Wherever possible, examiners should issue a first report on the parent application before issuing a first report on the additional application, in order to avoid complications at acceptance (see paragraph below).

Note: Examiners must not accept an application for a patent of addition until the parent application has been accepted ( Grant Requirements). Where there are outstanding objections to the parent application, examiners should state in their report that the opinion in respect of Chapter 7 of the Act is tentative pending resolution of the objections to the parent application. A report to this effect should be issued, even when the application for the patent of addition is otherwise in order for acceptance.

Special Considerations

A patent of addition cannot claim matter that was disclosed in the parent specification, as this would give rise to an objection of lack of novelty in the light of the parent.  However, an objection of lack of inventive step with respect to the parent is not applicable by virtue of sec 25 (see 2.19.3 “Improvement" and "Modification" and 2.19.6 Differentiation from the Parent for further information).

The specification of the patent of addition may contain a claim that specifically refers to the parent specification.  Such claims must be considered carefully to ensure that any reference is unambiguous.  Examiners should note, however, that it is often necessary to refer to a particular claim of the parent specification, in order to avoid ambiguity.

Where an application for a patent of addition is in respect of a specific apparatus for carrying out a method or process of the main invention, and essentially includes integers which function to perform all the steps of that process or method, the application may proceed as an application for a patent of addition.  However, if the apparatus claimed is of a general, rather than a specific, nature, the applicability of Chapter 7 is doubtful.  Cases of this kind should be referred to a supervising examiner.

Failure to Meet Patent of Addition Requirements

Where an application for a patent of addition does not meet the requirements of Chapter 7, e.g. the patent of addition is not an improvement in or modification of the main invention, examiners should object accordingly.  In this situation the patent request for the patent of addition may be amended under sec 104 so as to no longer invoke Chapter 7.  Amendment of the specification, and any statement relating to entitlement, may also be necessary.  Any subsequent report on an application so amended is to report as though the application has not invoked Chapter 7, including, where appropriate, that an inventive step objection may now apply based on the earlier parent application.

Conversion to Patent of Addition

A patent request for an ordinary application for a patent may be amended under sec 104 to an application for a patent of addition in rebuttal of an examiner's objection (e.g. lack of inventive step), provided that all the requirements of Chapter 7 are satisfied (see also Amending a Patent Request to a Patent Request for a Patent of Addition).

Further information on the examination of additional applications is provided in:

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