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European patent prosecution – impact of the International Searching Authority (ISA)

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When entering the European regional phase from the PCT phase the choice of the international searching authority (EPO or non-EPO international searching authority) has an impact on the actions that are required shortly after regional phase entry and also an impact on the fees that are payable. This article provides a high level overview of the main points of difference.

Summary Table

The table below outlines the main points of difference between cases where the EPO was the international searching authority (ISA) and cases where the EPO was not ISA.

Bloomberg table

Waiving right to communication under Rule 161(1) or (2) EPC

It is possible to accelerate the processing of a Euro-PCT application by waiving the right to the communication under Rule 161 (1) or (2) EPC. The waiver can be submitted by simply ticking the relevant box on the form for entry into the European phase (Form 1200) or in a separate signed statement.

Where the EPO was ISA, the waiver will only be effective if a response to the written opinion has already been submitted (i.e. on entry to the European phase) or if the written opinion is positive. Following the waiver, the EPO will not issue a communication under R161(1) or (2) EPC and the application will proceed straight to examination (where the EPO was ISA) or supplementary search (non-EPO ISA).

Partial Search by ISA

Where the ISA (either EPO or non-EPO) has found there to be a lack of unity in the claims and has conducted a partial search, applicants will have the right to have a search performed by the EPO on any invention claimed in the application documents which are to serve as the basis for the procedure in the European phase.

Where ISA = Non-EPO (Rule 164(1) EPC)

The EPO will draw up a partial supplementary search for in respect of the first invention mentioned in the claims. The EPO will then invite the applicant to pay a further search fee (within 2 months) for any of the other inventions they wish to get searched. For this reason it is advised to have the most important claims listed first.

Where ISA = EPO (Rule 164 (2) EPC)

The EPO will invite, in the first examination report, the applicant to pay a search fee (within 2 months) for any invention that was not covered by the international search by the EPO.

In either case, the applicant will only be able to pursue the application for an invention for which an EPO search has been conducted.


This article was first published (as “How Choice of ISA Will Change European Prosecution”) on 12/2018 by Bloomberg Law. Reproduced with permission from Bloomberg Law, https://www.bna.com/bloomberglaw. Copyright (c) 2018 by The Bureau of National Affairs, Inc, https://www.bna.com/

1 Comment

  1. Suleman says:

    In the case of a partial search by the EPO as ISA, it should be borne in mind that the Rule 164 Communication will only refer to paying additional search fees for inventions which are still covered by the pending claims. If an unsearched invention has been deleted from the claims before then, it is not mentioned in the Rule 164 communication and so it may not be possible to have it searched at that stage (which is probably not going to be needed anyway)

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