Welcome to the new version of the Patents Manual. Please note there are changes to the numbering and sequence of the chapters and pages in the manual. You are encouraged to take the time to explore and familiarise yourself with this new structure. Box IV Unity of Invention

Date Published

Key Legislation:

Administrative Instructions under the PCT:

  • s206 Unity of Invention

Regulations under the PCT:

  • Rule 13 Unity of Invention
  • Rule 66 Procedure before the International Preliminary Examining Authority
  • Rule 68.1 No Invitation to Restrict or Pay
  • Rule 68.2 Invitation to Restrict or Pay
  • Rule 88 Amendment of the Regulations

PCT ISPE Guidelines:

Where lack of unity of invention is evident, it may, depending on the circumstances, be appropriate to issue an "Invitation to Restrict or Pay Additional Fees" (form PCT/ISA/206 and PCT/IPEA/405). It should be noted that separate invitations apply during International Search and Preliminary examination stages. Due to the strict time limits for establishing the ISR/ISO and IPRPII this issue should be considered at the earliest possible opportunity. [Rule 13 Rule 66 Rule 68 Ad. Inst. 206 PCT/GL/ISPE/12 at Chapter 10]

The requirements for unity of invention are specified in Rule 13 and discussed fully in 6.1.4 Unity of Invention.

An invitation to pay additional fees should not be issued by an IPEA (the circumstances in which an ISA should issue an invitation are discussed in Issuing the Invitation to Pay Additional Search Fees) where:

  • the ISA has not raised the issue of lack of unity; note that international preliminary examination is not applicable to claimed inventions that were not the subject of the ISR.
  • the ISA raised the issue of unity and additional fees were not paid; in this case examination is to proceed in respect of those claims which were searched, the IPEO or IPRPII clearly specifying for the other claims that no ISR is available and thus no meaningful opinion can be given [PCT/GL/ISPE/12 at para 17.62]. This should be done by inserting a comment similar to PERP [T25] following the observations on lack of unity in item 3 of Box IV.

In relation to a PCT application undergoing international preliminary examination, an invitation to pay additional fees may be issued where:

  • the ISA raised the issue of lack of unity and the applicant paid additional search fees for further searching and examination, or
  • the ISA found there was lack of unity but did not invite additional search and examination fees for additional inventions.

The decision on whether to issue an Invitation in these circumstances is somewhat discretionary, and should be based on likely additional effort involved and hence costs incurred in considering the additional invention(s). The following may be relevant to the decision:

  • the number of citations relevant to each invention,
  • whether citations are common to different inventions,
  • the number and nature of claims for each invention, and
  • the perceived effort needed to deal with each invention through the examination stage (opinions and report).

As a guide, if the overall additional effort involved to examine an additional invention is estimated to require more than about 2 hours of time over the first invention then an invitation should be issued.

Where it is considered that an invitation to pay additional fees should issue, the examiner will complete form PCT/IPEA/405 and gain approval from their Supervising Examiner following the procedures listed in the RIO for Patents Manual.  The Supervising Examiner is the authorised officer for an invitation to pay and the time limit for a response to an invitation is one month. [Rule 68.2].

The invitation must include a logically presented, technically reasoned statement setting out the basis for the finding of lack of unity. The requirements in this regard are the same as specified in Issuing the Invitation to Pay Additional Search Fees. The invitation must also include at least one possible restriction of the claims which would avoid the objection of lack of unity. The invitation should also include the basis for the number of additional examination fees invited and, where applicable, indicate which inventions can be examined with another without requiring a separate examination fee.

Example as in: Annex F - Invitation to Restrict/Pay Additional Fees - Unity illustrates the required level of detail.

As the applicant's response will determine which of the claimed inventions will be examined, the international preliminary examination should be largely deferred until a response is filed or the time limit for response expires.

Where an invitation issues, the time limit for establishing the report does not alter.

If the applicant fails, within the time allowed, to restrict the claims or pay the additional fees, the international preliminary examination should proceed in relation to the main invention or where this is not readily apparent the invention first mentioned in the claims. Otherwise, the examination is to be carried out for those claimed inventions for which fees are paid or for the invention defined in the restricted claims. [PCT/GL/ISPE/12 at para 10.75]

Where the applicant pays the additional fees under protest, the PCT unit will forward the case to the Assistant General Manager (AGM) with responsibility for the section where the protest occurred.  The AGM will arrange for the protest to be reviewed by an independent supervising examiner.  Based on this review and the examiner’s comments, the AGM will decide whether the applicant’s protest should be upheld. The international preliminary examination should proceed in relation to all the claimed inventions for which fees are paid. [PCT/GL/ISPE/12 at para 10.78]

A protest may be upheld and the fees refunded (fully or in part), for several reasons including:

  • that, having regard to the facts of the case and the PCT Rules, there is no lack of unity,
  • the invitation fails to give either sufficient or substantially correct reasons for the finding of lack of unity and the lack of unity is not manifestly obvious from the claims themselves,
  • that the amount of the additional fees, in the circumstances, is excessive.

Irrespective of whether an Invitation has been issued, where unity of invention is lacking this observation must be included in the ISO, all IPEOs and the IPRPII for which that is the case. The ISO, IPEO and IPRPII do not require an observation on lack of unity in Box IV if no lack of unity has been found, except if any entry in Item 1 of Box IV of IPEO or IPRPII has been required to be made. As a corollary to this checkbox IV in Item 2/3 at the front page of the opinion/report, respectively, should only be crossed if Box IV of the opinion or report contains an observation. [Rule 68.1 PCT/GL/ISPE/12 at para 17.38, 17.39].

It should be noted that in cases whereby the ISA found lack of unity in establishment of the ISR/ISO and issued an invitation to pay additional fees, there is no requirement to check Item 1 of Box IV (relating to a response to an invitation to pay) of the IPEO or IPRP unless the IPEA also issued a further (i.e. separate) invitation to pay additional fees. If the IPEA did not issue a further invitation for additional fees, this item should be left blank.

Amended Reasons

Amended Reason Date Amended

Published for testing

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