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PCT applications

The Patent Cooperation Treaty facilitates filing of applications.

The Patent Cooperation Treaty (PCT) has the aim of facilitating filing, searching and examination procedures of so called International Patent Applications in all countries which have ratified the Treaty.

An International Patent Application may designate groups of countries and particularly in the contracting states of the European Patent. In such a case, all the countries of the European Patent Convention (EPC) are automatically designated.

In Europe, the International Searching Authority (ISA) and the International Preliminary Examination Authority (IPEA) is the European Patent Office (EPO).


The PCT system allows an applicant to file an International Patent Application in his own language. If search and examination is to be made by the EPO, the filing language must be one of the EPO’s official languages (English, French and German).


a) Filing the application

The International Patent Application is filed with the Patent Office of the applicant’s domicile. The Patent Office with which the application is filed is known as the receiving Office.

b) Formal Examination

The receiving Office carries out an examination for questions of form, and makes sure that all the necessary fees have been paid, and all the supporting documents filed, in the manner and within the time period specified by the Treaty.

c) Search

Next, the receiving Office forwards the international application both to the International Office (WIPO) in Geneva and to a competent authority responsible for international search (the International Searching Authority - ISA). The US Patent Office, the Japanese Patent Office and the European Patent Office are among the competent International authorities according to the PCT. US and Japanese applicants filing at their national Patent Office (USPTO or JPO) may also request that the
European Patent Office be the International Searching Authority (ISA) for their International Patent Application.

During the search procedure as such, the authority responsible for the search (ISA) may forward comments to the International Office in Geneva and to the applicant, particularly in cases involving questions of lack of unity in the invention. Communications with the International Office in Geneva must be in French or English only.

An international search report is next sent to the applicant and to the International Office in Geneva, which translates it into English, in the event that the international application is published in a language other than English.

After studying the search report, the applicant has one opportunity to modify the claims in his application, by sending the modified claims to the International Office in Geneva.

d) Publication

The International Office in Geneva transmits the International application to all the designated Offices, together with the search report, which is accompanied if necessary by its English translation. The International Office publishes the International application and the search report. The publication cannot occur earlier than 18 months after the priority date of the application.

e) Optional preliminary examination

The applicant may request the issuance of a preliminary examination report in the form of a non-binding opinion, covering the following three points:

  • novelty
  • inventive step (non-obviousness)
  • suitability for industrial application

f) National or regional procedure

The national or regional procedure begins in each national or regional patent Office after the end of the search phase (in the designated Offices) or after the end of the examination phase (in the elected Offices). The applicant must transmit to each of the designated Office a translation of the international application in the official language of the country in question, and pay the national filing fees to the designated patent Offices. These formalities must be performed within a maximum time period of 30 months following the priority date applicable to the international application (or 321 months for the EPO).

In some countries among which are France, Belgium and Netherlands a national patent shall not be obtainable through the PCT system.

The designation of one of those countries in an international application is deemed to be a request for grant of a European Patent, governed by the Munich Convention (Euro PCT application).

The Applicant who wishes to obtain a national patent in those countries, must necessarily file a national patent application and not make use of the PCT system.


Those applications result from the entry into the European regional phase of PCT application filed outside Europe.

The "regional" or "national" phase at the EPO of PCT applications must be engaged within 31 months of the priority date.

The European patent application generally follows the examination and granting procedure of the EPO and is called a "Euro PCT" application. The following specific features can be noted.

1) Designation fees

In the PCT application, all the countries of the EPC are designated at once. When the regional phase of the Euro PCT application is engaged, designations of specific countries of the EPC together with payment of the individual designation fees must be performed within a time period of 31 months from the priority date.

It is also possible to pay extension fees for some European Countries in which the European patent protection can be extended within the same time period. The list of the contracting states of the EPC and the countries for which the European patent protection can be extended, is available on the web site:

2) Supplemental search

If the international search has not been performed by the EPO, a supplemental search report is issued by the EPO and a corresponding fee must be paid.

3) Examination request

A request for the examination by the EPO must be made within 6 months of publication of the international search report. Usually, this examination request must therefore be filed at the time of engaging the regional phase at the EPO. The examination fee must be paid at the same time.

During examination, the Examiner will rely upon the international preliminary examination report, particularly if the EPO acted as IPEA in which case the European examiner will normally be the same one who drafted said report.