May 2022 | No. 05/2022


Practical Advice

Options for maximizing prior art coverage in the context of searches carried out during the international phase

Q:  I am going to file an international application with the United States Patent and Trademark Office (USPTO) as receiving Office (RO/US), claiming priority of an earlier national application filed in the U.S.  I have received the results of the earlier search, which already give a good coverage of U.S. prior art.  Is there anything that I can do to broaden the coverage of the search in the international phase, in particular, to get a good coverage of prior art in Europe and Japan, so that I know as much as possible about relevant prior art before entering the national phase?

A: International Search

The applicant’s choice of International Searching Authorities (ISAs) is determined by the receiving Office with which he or she files the international application – in your case, the USPTO.1  Since you are going to file your international application with the RO/US, you can, at the time of publication of this Practical Advice, choose between the following seven ISAs:  the Australian Patent Office, the Federal Service for Intellectual Property (Rospatent) (Russian Federation)2, the Intellectual Property Office of Singapore, the Israel Patent Office, the Japan Patent Office, the Korean Intellectual Property Office and the United States Patent and Trademark Office.  As you have a choice of ISAs, you can select an ISA that is not the same Office as the one which carried out the search of the earlier national application (the USPTO), and by so doing, you might benefit from a prior art search using different resources from those used for your earlier application.

Please note that if you choose an Office other than the USPTO, the following factors should be considered before making your decision (details of which can be found in the corresponding part of Annex D of the PCT Applicant’s Guide at:  https://www.wipo.int/pct/en/guide/index.html):

  • the fees set by the chosen ISA – each ISA sets its own fees and these do vary;
  • the language in which the ISA is prepared to carry out the search, and whether the ISA will require a translation of the international application (although please note that all of the above‑mentioned ISAs are prepared to carry out searches of international applications in English);
  • whether the ISA is prepared to carry out a search on the subject matter of your international application;
  • whether you intend to file a demand for international preliminary examination with a particular International Preliminary Examining Authority (IPEA) – certain IPEAs will only act as IPEA if they were also chosen as ISA for the international application concerned; and
  • whether there is a limit on the number of international applications that a particular ISA is prepared to search when the international application concerned was filed with a particular receiving Office.

Let us take the example of choosing the Japan Patent Office (JPO) as ISA in order to benefit from a solid search of the prior art featuring in the documentation held at the JPO.  Without taking into account any applicable fee reductions, the (international) search fee at the JPO is currently 1,475 US dollars for an international application filed in (or translated into) English, compared to 2,180 US dollars for a search carried out by the USPTO, so in this case, the amount of the search fee would be lower at ISA/JP.  The JPO as IPEA will accept international applications filed with the USPTO and do not require that the international search be carried out by the JPO.  Please note, however, that the JPO does have a limit on the number of international applications filed at RO/US that it will search, and so you will need to check with the JPO that this limit has not yet been met.  For further details, please refer to Annex A(i) of the Agreement between the Japan Patent Office and the International Bureau of the World Intellectual Property Organization in relation to the functioning of the Japan Patent Office as an International Searching Authority and International Preliminary Examining Authority under the Patent Cooperation Treaty at: 


Supplementary international search

If you would like to further broaden the prior art search during the international phase, you could also request a supplementary international search from one or more of the Authorities which carry out supplementary international search (SISAs), irrespective of the Office with which the international application is filed (or the State of nationality and/or residence of the applicant(s)), but you cannot select the same Office as both ISA and SISA.  A request for supplementary international search must be filed at the IB.  The following 10 Offices are currently prepared to carry out supplementary international searches:  the Austrian Patent Office, the European Patent Office, the Federal Service for Intellectual Property (Rospatent) (Russian Federation)3, the Finnish Patent and Registration Office, the Intellectual Property Office of Singapore, the National Intellectual Property Authority, State Enterprise “Ukrainian Intellectual Property Institute (Ukrpatent)”, the Nordic Patent Institute, the Swedish Intellectual Property Office, the Turkish Patent and Trademark Office and the Visegrad Patent Institute.

The following factors should be considered before deciding which Office to use for the purposes of supplementary international search (details of which can be found in the corresponding part of Annex SISA of the PCT Applicant’s Guide):

  • the scope of documentation that can be searched at a particular Office;
  • the amount of the supplementary search fee charged by the SISA – each ISA sets its own fees and these may vary, depending on the scope of the supplementary search that it will carry out;
  • the language accepted for supplementary international search (although please note that all SISAs are prepared to carry out a supplementary international search on an international application in English); and
  • whether the SISA is prepared to carry out a supplementary search on the subject matter of your international application.

As an example, you could choose the European Patent Office (EPO), which will provide you with a search of the PCT minimum documentation as well as the documents held in its search collection.  It will accept international applications in English, French or German, and currently charges 1,912 Swiss francs for such a search, and there is also a supplementary search handling fee (payable for the benefit of the IB) of 200 Swiss francs (this is the same amount for all SISAs).

Although diversifying the searches in the international phase to maximize the prior art coverage might add to the costs that you will incur in the international phase, it should provide you with more complete and extensive search results, and guide you even better in your future decisions.  Note also that certain designated Offices offer fee reductions in the national phase for international applications for which an international search report or supplementary international search report has been established by certain Offices (further information is available in the corresponding National Chapter (Summary) of the PCT Applicant’s Guide).

  1. If an applicant decides to file the international application with the International Bureau as receiving Office (RO/IB), the competent ISA(s) is (or are) the same as would have been competent if the international application had been filed with the national Office of, or acting for, a Contracting State of which the applicant (or applicants) is a resident or national (PCT Rule 35.3).  Note that there may be a wider choice of ISAs when filing with RO/IB if there are two or more applicants from different PCT Contracting States.
  2. Please refer to the statement dated 22 March 2022 on the USPTO website (https://www.uspto.gov/about-us/news-updates/uspto-statement-engagement-russia-and-eurasian-patent-organization).
  3. Please refer to the statement dated 22 March 2022 on the USPTO website (https://www.uspto.gov/about-us/news-updates/uspto-statement-engagement-russia-and-eurasian-patent-organization).