PA 01/2012: The benefits of requesting supplementary international search

WARNING: Although the information which follows was correct at the time of original publication in the PCT Newsletter, some information may no longer be applicable; for example, amendments may have been made to the PCT Regulations and Administrative Instructions, as well as to PCT Forms, since the PCT Newsletter concerned was published; changes to certain fees and references to certain publications may no longer be valid. Wherever there is a reference to a PCT Rule, please check carefully whether the Rule in force at the date of publication of the advice has since been amended.

Q: I have seen that it is possible to request that a supplementary international search be carried out on an international application, in addition to the main international search. Before I decide whether or not to incur the additional expense that requesting this service would entail, please could you let me know what the benefits of requesting such a search are?

A: You will need to weigh the benefits of the additional information which you may obtain from one or more supplementary searches against the extra cost that would be incurred. Some of the potential advantages of supplementary search are outlined below.

Even though the main international search is of high quality and covers not only the PCT minimum documentation but also all the additional documentation which would be searched by the International Searching Authority (ISA) in its role as a national Office, a supplementary search should further reduce the risk of new prior art being cited in the national phase for it includes all documentation that the Authority specified for supplementary search (SISA) would search in its role as national or regional Office, enabling you to be better informed about the chances of obtaining a patent before you incur national phase expenses. (Note that the time limit for establishing the supplementary international search report is 28 months from the priority date, and so you should receive it before you have to make a decision about whether or not to enter the national phase in a particular country.)

A growing problem in finding relevant prior art is that the range of languages in which original technical disclosures are made is constantly increasing, and even though machine translation can be used to a certain extent to translate disclosures, this is not as reliable as having access to the results of a search carried out by an examiner who understands the original language. Therefore, given that no single Office is capable of searching the whole of the PCT minimum documentation in its original language (nor indeed the large volume of other patent and non patent literature containing original disclosures), supplementary search permits the applicant to have a search carried out by an ISA which specializes in documents in a particular language or languages. For example, if the main international search has been carried out by the Japan Patent Office, but there are a large number of patent documents in Russian which cover the technology relevant to the international application, it may be useful to request that the Federal Service for Intellectual Property, Patents and Trademarks (Rospatent) (SISA/RU) carry out a supplementary search.

One advantage of the supplementary search system is that, unlike the requirements for the choice of ISA, the choice of SISA is not limited to a specific International Authority (or Authorities) which has been specified by the receiving Office – the applicant is free to request any of the International Authorities which carry out supplementary searches. The following Offices offer supplementary search in respect of international applications filed in, or translated into, the languages indicated:

Austrian Patent Office                                          English, French, German

European Patent Office                                       English, French, German

National Board of Patents and Registration
  of Finland                                                             English, Finnish, Swedish

Federal Service for Intellectual Property,
  Patents and Trademarks (Rospatent)           English, Russian

Swedish Patent and Registration Office         Danish, English, Norwegian, Swedish

Nordic Patent Institute                                         Danish, English, Icelandic, Norwegian,

You will need to think carefully about which SISA you wish to request to carry out the supplementary search. This decision may be based on the scope of the supplementary search as well as the cost of the search. It is up to the individual Authorities offering supplementary search to define the scope of the service which they are offering, and for the applicant to decide which (if any) of those services meets the needs of the particular application (for information on the scope of the supplementary search before each SISA, see the relevant Annex SISA in the PCT Applicant’s Guide ( Some SISAs may offer a search which is focused on documentation in languages in which they specialize, while others may offer a full search, covering their entire documentation as they would do if they were conducting a main international search. Note also that, although the supplementary search handling fee, payable for the benefit of the International Bureau (IB), is the same in the case of all SISAs (200 Swiss francs), each SISA sets its own supplementary search fee for the service, therefore some may be more expensive than others (see the PCT fee tables in this issue for details about the fees payable in respect of the different SISAs). You may also incur translation costs where the international application is not available in a language in which that Authority will carry out supplementary search.

The amount you are willing to spend on obtaining a comprehensive search before entry into the national phase may also depend on the commercial viability of a particular application, and the number of countries in which you would like your invention to be protected. The more countries in which you wish to have protection, the more you may be willing to spend on obtaining complete search results before incurring the relatively high costs of entering the national phase in each country. Furthermore, whether or not you decide to request supplementary search may depend on whether you already have results from other searches which may already have been made by national or regional patent Offices, independent search services or your own search efforts.

Note that once the international application has been published, and the supplementary international search report has been received, it is made available for public inspection by the IB on PATENTSCOPE (

It is not expected that supplementary search be requested routinely, but strategically after consideration of the results of the main international search, the commercial importance of the particular application and the amount of prior art in the particular technical field which is known to be published in a language in which the main ISA is not skilled, or which does not fall within the scope of the ISA concerned. It is a way of providing extra information where the additional expense in the international phase is worthwhile.