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  • Gagandeep Singh

Deciphering the PCT Application Process

While there is no such thing as a world-wide patent, there is something that approximates a world-wide patent application that can result in a patent being obtained in most countries around the world. This patent application is known as an International Patent Application, or simply an International Application. The international treaty that authorizes the filing of a single patent application to be treated as a patent application in countries around the world is the Patent Cooperation Treaty, most commonly referred to as the PCT.


What is the Patent Cooperation Treaty (PCT)?


The PCT is an international treaty with more than 150 Contracting States. The PCT makes it possible to seek patent protection for an invention simultaneously in a large number of countries by filing a single “international” patent application instead of filing several separate national or regional patent applications. The granting of patents remains under the control of the national or regional patent offices in what is called the “national phase”.


The Patent Cooperation Treaty, or the PCT as it is typically referred to, came into existence in 1970. It is open to States party to the Paris Convention for the Protection of Industrial Property (1883).  The Treaty, which like any other Treaty is a legal agreement entered into between various countries.  The purpose of the PCT is to streamline the initial filing process, making it easier and initially cheaper to file a patent application in a large number of countries. By filing through the PCT process, patent protection for an invention in every country that is a member to the Treaty can be enforced.


PCT Patent Application Procedure:


1. Filing:

An international patent application may be filed by anyone who is a national or resident of a Member Country.  A Member Country, also referred to sometimes as Contracting States, are simply those countries that are members to the international treaty. The appeal of the PCT process is that it enables patent applicants to file a single patent application and have that single, uniform patent application be treated as an initial application for patent in any Member Country. This single, uniform patent application is what is referred to as the international application.

The international application must be filed in an authorized Receiving Office. The Receiving Office functions as the filing and formalities review organization for international applications. The Patent Offices of the countries that are members to the PCT are called Receiving Offices (For e.g. USPTO in US).


2. International Phase:

An “International Searching Authority” (ISA) or International Preliminary Examining Authorities (IPEA) (one of the world’s major patent Offices) identifies the published patent documents and technical literature (“prior art”) which may have an influence on whether the invention is patentable, and establishes a written opinion on the invention’s potential patentability.

The purpose of the international search is to discover relevant prior art. “Prior art” consists of everything which has been made available to the public anywhere in the world by means of written disclosure (including drawings and other illustrations); it is “relevant” in respect of the international application if it can help determine whether or not the claimed invention is new, whether or not it involves an inventive step (in other words, whether it is or is not obvious), and whether the making available to the public occurred prior to the international filing date. The international search is made on the basis of the claims, with due regard to the description and the drawings (if any) contained in the international application. The results of the international search are set out in the international search report.


International Searching Authority may refuse to search certain subject matter:


The International Searching Authority is not required to perform an international search on claims which relate to any of the following subject matter:

(i) scientific and mathematical theories, (ii) plant or animal varieties or essentially biological processes for the production of plants and animals, other than microbiological processes and the products of such processes, (iii) schemes, rules or methods of doing business, performing purely mental acts or playing games, (iv) methods for treatment of the human or animal body by surgery or therapy, as well as diagnostic methods, (v) mere presentation of information, and (vi) computer programs to the extent that the Authority is not equipped to search prior art concerning such programs. However, certain International Searching Authorities do, in practice, search these fields to varying extents - for example, several International Searching Authorities search subject matter which is normally searched under the national (or regional) procedure.


International Search Report:


The international search report must be established within three months from the receipt of the search copy by the International Searching Authority or nine months from the priority date, whichever time limit expires later.


The international search report contains, among other things, the citation of the documents considered relevant, the classification of the subject matter of the invention (according to the International Patent Classification) and an indication of the fields searched (those fields being identified by a reference to their classification) as well as any electronic data base searched (including, where practicable, the search terms used). Citations of particular relevance must be indicated specially. Citations which are not relevant to all the claims must be indicated in relation to the claim or claims to which they are relevant. If only certain passages of the document cited are relevant or particularly relevant, they must be identified, for example by an indication of the page on which, or the column or lines in which, the passage appears. It is important to note that an international search report must not contain any expression of opinion, reasoning, argument or explanation of any kind whatsoever.


Supplementary International Search (Optional):


Supplementary international search permits the applicant to request, in addition to the international search carried out (the “main international search”), one or more supplementary international searches each to be carried out by an International Authority (the “Authority specified for supplementary search”) other than the International Searching Authority that carries out the main international search.

Requesting supplementary international search reduces the risk of new prior art being cited in the national phase. The increasing diversity of prior art in different languages and different technical fields means that the Authority carrying out the main international search is not always capable of discovering all of the relevant prior art. Requesting one or more supplementary international searches, during this early phase of the patent prosecution, expands both the linguistic and technical scope of the search. In addition, it may also be possible to have the supplementary search carried out in a State where they are likely to enter the national phase later on.

A supplementary search request must be filed with the International Bureau and not with the Authority specified for supplementary search. The International Bureau will transmit the request to the Authority specified for supplementary search once it has verified that all formal requirements have been complied with.


International Publication:


As soon as possible after the expiration of 18 months from the earliest filing date, the content of the international application is disclosed to the world. International applications are published by the International Bureau.


Publication of international applications filed under the PCT takes place wholly in electronic form. The published international application will include any declaration filed under Rule 4.17 and, if available at the time of publication, the international search report or declaration by the International Searching Authority to the effect that no international search report will be established, and also any amendment, including any statement, under Article 19.

Each published international application is assigned an international publication number consisting of the code WO followed by an indication of the year and a serial number (for example, WO 2004/123456).


The published international application in electronic form is available on PATENTSCOPE.


International Preliminary Report on Patentability (IPRP) (Optional):


International preliminary examination is a second evaluation of the potential patentability of the invention.

If you wish to make amendments to your international application in order to overcome documents identified in the international search report and conclusions made in the written opinion of the ISA, international preliminary examination provides the only possibility to actively participate in the examination process and potentially influence the findings of the examiner before entering the national phase – you can submit amendments and arguments and are entitled to an interview with the examiner. At the end of the procedure, an international preliminary report on patentability (IPRP Chapter II) will be issued.


3. National Phase:


The national phase is the second of the two main phases of the PCT procedure. It follows the international phase and consists in the processing of the international application before each office of or acting for a Contracting State that has been designated in the international application. In each designated State the international application has the effect of a national (or regional) application as from the international filing date, and the decision to grant protection for the invention is the task of the Office of or acting for that State (the “designated office”).


Designated Office: The national office of a Contracting State is a “designated office” if the State is “designated” in the international application for national protection. The filing of a request constitutes the designation of all Contracting States that are bound by the Treaty on the international filing date.


Elected Office: Where a demand for international preliminary examination is filed, the term “elected office” is used - instead of the term “designated office” - to denote the office of or acting for a State in which the applicant intends to use the results of the international preliminary examination. Since only designated States can be elected, all elected offices are necessarily also designated offices.


Time Limit:

  • The time limit for entering the national phase before a designated office is 30 months from the priority date. In respect of certain designated offices, the applicable time limit is 20 months, not 30 months because of the incompatibility, for the time being, of the modified PCT provision (PCT Article 22(1)) with the relevant national law; those offices made a declaration of incompatibility which will remain in effect until it is withdrawn by the respective offices.

  • The time limit for entering the national phase before an elected office is 30 months from the priority date. The time limit is normally 30 months from the priority date, the same time limit for entering the national phase as that which applies in the case of a designated office which has not been elected. In respect of the designated offices, for which the 20-month time limit applies, the time limit is 30 months from the priority date if the applicant files a demand for international preliminary examination prior to the expiration of 19 months from the priority date. The national law applied by each elected office may fix a time limit which expires later than 30 months from the priority date.

What Must be Done by the Applicant Before the Start of the National Phase?

  • Payment of the national fee

  • Furnishing of a translation, if prescribed

  • In exceptional cases (if a copy of the international application has not been communicated to the designated office under), furnishing of a copy of the international application, except where not required by that office.

  • In exceptional cases (if the name and address of the inventor were not given in the request when the international application was filed, but the designated office allows them to be given at a time later than that of the filing of a national application), furnishing of the indication of the name and address of the inventor.

  • A translation of the international application must be furnished if the language in which it was filed or published is not a language accepted by the designated office.

Gagandeep advises clients on infringement investigations related to electronics, telecommunications and software. He has a Master’s degree in Electrical, Electronics and Communications Engineering and a Bachelor's degree in Electronics Engineering. His interest areas are Internet of things (IoT), Semiconductor, Operating Systems (Android/iOS/Windows/Linux), Embedded Software and Sensor Networks.


Keywords: pct application search, pct application process, patent cooperation treaty, pct procedure, pct patent search, pct countries, patent pct, wipo pct search, pct application patent


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