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6.1.4.10 Unsupported, Unclear, Long and/or Complex Claim Sets with Clear Lack of Unity

Date Published

Where it is apparent that only one general inventive concept is described and lack of unity arises merely because of claims that are not supported by the description and/or are not clear and concise, the procedures in 6.1.7.1.1 Claim Interpretation; Broad Claims; PCT Articles 5 and 6 are to be followed. In these circumstances it will generally not be necessary to issue an invitation to pay additional search fees but the technical lack of unity may be noted in the search report as in 6.1.4.12 Completing the Search Report. [PCT/GL/ISPE/12 at Chapter 9, para 9.34].

In other cases, in which the claims are large in number, complex, or their nature encompasses a range of separate inventions, it will be necessary to directly address lack of unity. In many such cases, however, due to the nature and complexity of the claims, there is a risk that the applicant will not want the first mentioned invention to be searched and/or they will disagree as to the number and identity of the inventions.  Frequently, therefore the task of preparing the invitation will be very time consuming and ultimately wasted if the applicant does not wish to pursue additional inventions identified.

General Approach

As the specifics of each case vary, examiners should adopt a flexible approach when developing a strategy to progress these cases. Examiners should therefore consult with their supervising examiner and develop together an approach tailored to the specific circumstances of the case.  

In general, however, preliminary consultation with the attorney of the issues surrounding the finding of lack of unity will usually result in a more efficient process and effective search strategy.

Thus, the following steps should be included in the strategy adopted.

  1. Preliminary contact with the attorney by phone to discuss how best to progress the search. This discussion should include:
  • Explaining the basis of the finding of lack of unity and discussing the justification for the additional search fees; and
  • Inviting the applicant to nominate what they consider to be the main invention, i.e. the invention they would prefer to be searched for the fee already paid.

2. Where, following discussion with the attorney (or if such discussion cannot take place), a finding of lack of unity still applies and a search encompassing the whole of the claims cannot be carried out for the single search fee already paid, the examiner should issue an invitation to pay additional search fees (ITP) using form PCT/ISR/206 including a level of detailed explanation appropriate in the light of the discussion with the attorney. This may either be:

  • an *abbreviated ITP (see below), where there is negotiated between the examiner and the attorney, a fully agreed position on the finding of lack of unity and the invention groups identified; or
  • a comprehensive ITP as discussed at 6.1.4.9 Issuing the Invitation to Pay Additional Search Fees, fully addressing any issues raised by the applicant or their attorney, in all other cases.  

For example, a comprehensive ITP could be required if the attorney:

  • indicates disagreement with the finding on unity;
  • indicates additional fees will be paid under protest; or
  • provides no comments.​​​​​​​

*Note: An abbreviated invitation to pay additional fees need only briefly discuss the inventive concepts, list the inventions identified in the claims and address any specific applicant’s comments, rather than providing the detailed discussion of lack of unity required in a comprehensive ITP.

In all cases: examiners should record on the file, as part of the invitation or as a record of the conversation with the attorney, sufficient information to clearly explain the basis for the finding of lack of unity and the justification for the additional search fees.

Note that in all cases Box III of the search report should clearly identify the invention(s) searched and, if excluding the first mentioned invention, that this was at the request of the applicant. For example, no required additional search fees were timely paid by the applicant. Consequently, this international search report is restricted to the invention covered by claims Nos.: 10-20, at the request of the applicant.

Amended Reasons

Amended Reason Date Amended

Published for testing

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