Thinking Globally: International Search Reports

  • January 2, 2018

One of the benefits of filing an international patent application under the Patent Cooperation Treaty (PCT) is obtaining an International Search Report (ISR) listing relevant prior patent publications and articles, and a Written Opinion by an International Searching Authority (ISA).

The ISA will:

  • classify the invention
  • consider whether the application contains more than one invention
  • determine whether sequence listings are needed for the international search (in the case of biotechnology applications)
  • consider whether the Applicant has requested prior searches be used
  • determine the title and abstract of the PCT application
  • perform the search and prepare the ISR and Written Opinion.

Choosing a Searching Authority

Depending on the patent office in which an international patent application is received, some Applicants may have a choice as to the ISA. For instance, PCT applications correctly filed with the United States Patent and Trademark Office as Receiving Office can choose between the Searching Authorities located in Australia, Europe, Israel, Japan, South Korea, Russia, Singapore and United States.

Choosing which ISA to use can sometimes depend on preference, cost, patent subject matter, and/or patent claim structure. Certain differences between searching authorities may assist Applicants in making this division. One such difference is the cost of each ISA. This difference is relatively easy to compare and is typically a concern for most Applicants. Search fees can range from about $700 in Russia, to more than $2,200 for a search by the European Patent Office (as of January 2018).

However, if possible, the decision to use a particular searching authority should not be based on cost alone. Patent subject matter can also be a determining factor in choosing an ISA. It is also important to note the restrictions of some ISAs regarding the subject matter they are able to search. ISAs are not obligated to perform searches or give an opinion relating to subject matter that is not locally patentable.

For instance, in Europe, methods for treatment of a human or animal body by surgery or therapy, and diagnostic methods practiced on the human or animal body, are specifically excluded from patentability. Alternatively, Australia allows “method of treatment” claims. In the US, the claim structure must be taken into consideration since multiple dependent claims shall not serve as a basis for any other multiple dependent claim, while on the other hand, Europe allows this claim structure.

Paying Additional Search Fees

At times, the ISA will find more than one invention in an application. In this case, they will invite the Applicant to pay additional search fees. When faced with an invitation to pay additional search fees, the Applicant has several options:

  • Proceed with first group of claims and pay no additional fees.

If no additional search fees are paid, the ISA will finalize the preliminary ISR and Written Opinion provided with the invitation to pay additional fees.

Once the ISR has been finalized, the Applicant then has the option of amending the claims for publication by submitting claim amendments directly to the International Bureau within two months of the mailing of the ISR. Note: no new matter may be introduced, and the Applicant must point out the differences between the originally filed claims and the amended claims and must also point out the basis for the amendments in the application as originally filed. No official fee is charged for these amendments (Article 19 Amendments).

If Article 19 Amendments are filed, the application will publish with the amended claims (or will re-publish if amendments occur after initial publication). Any arguments and/or statements filed with the amendments will be publicly available, but the ISA will not provide an additional search based on the amended claims.

These amendments can then be considered when entering the national phase in the desired countries.

Whether or not Article 19 Amendments are filed, the Applicant also has the opportunity to demand examination under Chapter II of the PCT.

It is possible to amend claims and the specification at the time of demanding examination (Article 34 Amendments), however the International Preliminary Examination Authority (IPEA) is not obligated to examine any claims that were not subject to a search, and it is possible that the IPEA may also invite payment of additional examination fees if they find a lack of unity. The deadline to request Chapter II examination is either three months from the mailing of the ISR or 22 months from the earliest priority, whichever is later. The cost for filing a demand for Chapter II examination is dependent upon the IPEA.

The Article 34 Amendments can also be considered when entering the national phase.

Many Applicants elect not to pay the additional search fees and defer claim amendments until national phase filing of the application. Amended claims may be submitted at the time of national phase entry and, if necessary, additional search fees and/or divisional applications can be filed to capture all subject matter in the desired jurisdictions.

  • Proceed with the first group of claims and pay some or all of the additional claim fees.

The ISA will proceed to complete the searches and finalize the ISR and Written Opinion for which additional fees have been paid.

The Applicant has the same options of filing Article 19 Amendments and/or demanding Chapter II examination with Article 34 Amendments and/or amending the claims upon national phase entry as discussed above. The Applicant can choose which invention to focus on and file divisional applications to cover the additional inventions.

  • Pay some or all of the additional fees under protest.

If the Applicant believes that the finding of lack of unity is not in accordance with PCT Rules and Regulations, the Applicant can protest the additional search fees.

In order to protest, a reasoned statement to the effect that the application complies with the requirement of unity of invention or that the amount of the required additional fees is excessive must be filed. The protest will be reviewed (possibly by the same Examiner who issued the invitation), and if the protest is found justified, the total or part of the additional fees will be refunded. The protest fee is determined by the ISA.

The ISR and Written Opinion will contain the groups of claims for which additional fees were paid regardless of the outcome of the protest.

The Applicant has the same options of filing Article 19 Amendments and/or demanding Chapter II examination with Article 34 Amendments and/or amending the claims upon national phase entry as discussed above.

It is important to note that regardless of whether the ISA has found additional inventions, the Applicant has the same options upon receipt of their ISR, namely:

  • filing Article 19 Amendments; and/or
  • demanding Chapter II examination with Article 34 Amendments; and/or
  • amending the claims upon national phase entry.

Advantages of receiving a positive ISR

One advantage of receiving a positive ISR is being able to participate in the Patent Prosecution Highway (PPH). When an application is filed internationally, the Applicant has little control over the timeline of prosecution and grant of the application. Therefore, it is beneficial to take advantage of the work-sharing and international efforts that allow requests for accelerated processing in the national phase.

When a national application is filed in any of the PPH-PCT participating patent offices, the Applicant can request accelerated examination, using the positive ISR received in the international stage. Patent examiners may then make use of the search and opinion issued in the international application, including the Written Opinion of the ISA; the Written Opinion of the IPEA; or the International Preliminary Report on Patentability.

The participating PPH-PCT offices include European Patent Office, Japan Patent Office, Korean Intellectual Property Office, State Intelligence Property Office of the Peoples Republic of China, United States Patent and Trademark Office, among others.

The Applicant can generally obtain a final action more quickly in the participating patent offices by requesting that an application be processed under PPH agreements. Reusing search and examination results can facilitate the prosecution of the application, but the decision to grant a patent remains under the control of the national or regional offices.


Regardless of which ISA is chosen, the findings in the ISR and the Written Opinion are non-binding. The various countries designated in the application may or may not take these findings and/or opinions into consideration. Many of the countries will prepare their own search and will draw their own conclusions regarding patentability, and it is possible to amend the claims either at the time of entry or prior to examination. However, the findings and opinions received during the international phase may provide the Applicant with valuable insight into what aspects of their invention(s) may be more likely to be patentable, and help to shape a global patent strategy.

It is important to note that all claims remain part of the international application, whether or not they are considered in the ISR or Written Opinion.

Your patent attorney/agent can assist you with the appropriate international patent strategy for your invention.


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