Analyzing the PCT Filing Procedure


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. By the name “international” it should not be confused with an international grant of patent. The granting of patents remains under the control of the national or regional patent Offices in what is called the “national phase”.

Current Trends in PCT Filing

The Patent Cooperation Treaty was signed on the last day of the conference on 19 June 1970. The Treaty entered into force on 24 January 1978, initially with 18 contracting states. In 2019, 153 states were members of the PCT, and applicants from 127 countries across the six geographical regions of the world filed PCT applications at 87 receiving offices (ROs). The 153rd country to enter the PCT is Samoa, on 2nd October 2019. Despite this broad geographical spread, most filing activity is concentrated in a small number of economies. Combined, the top 10 ROs accounted for nearly 94% of applications received in 2019. With 60,993 filings, the China National Intellectual Property Administration (CNIPA) received the highest number of PCT applications. It was followed by the United States Patent and Trademark Office (USPTO), the Japan Patent Office (JPO), the European Patent Office (EPO), the Korean Intellectual Property Office (KIPO), and the International Bureau (IB) of WIPO.

With 58,990 PCT applications, applicants residing in China filed the most applications in 2019. This was the first year since the PCT System began operating in 1978 that applicants from the United States of America (U.S.) moved down to second place, with 57,840 PCT applications filed. They were followed by Japan, Germany, and the Republic of Korea (figure 2). Combined, these top five countries accounted for 78.2% of all PCT applications filed in 2019. Driven mainly by a rapid increase in filings by applicants from China, Japan, the Republic of Korea, and the U.S., the combined share of the top five users of the PCT System has increased every year for the last decade.

[Image source: WIPO]

Filing Procedures-

  • Filing

The first step is filing at the competent patent office, commonly known as the Receiving Office (RO). The filing in the RO must be done within 12 months from filing the local application. The application filed is called an International Patent Application or simply, PCT Application. As per the rule, at least one applicant has to be national or residing at the PCT Contracting State. Also, the PCT application has to be filed in one language only, which is dependent on the country chosen for International Search. Every PCT application is accorded with a PCT filing date.

  • International Search

The next procedure comes up with conducting International Search. The applicant can choose with any International Searching Authority (ISA) from among the list. This is the most important part of the PCT application because it accords the applicant with a search report for patentability of the invention. The ISA has to establish and provide the International Search Report (ISR). The high quality of the search is assured by the standards prescribed in the PCT for the documentation to be consulted, and by the qualified staff and uniform search methods of the ISAs, which are all experienced patent Offices. The applicant also receives a written opinion. The written opinion, with the international search report, helps to understand and interpret the results of the search report with specific reference to the text of international application, being of special help in evaluating the chances of obtaining a patent. The process has to be done within 16 months from the date of filing the local application.

  • International Publication

The PCT application is published by the International Bureau, WIPO. The publication is done within 18 months of filing the local application or the priority date, whichever is earlier.

  • Supplementary International Search (optional)

A second ISA identifies, at your request, published documents that may not have been found by the first ISA which carried out the main search because of the diversity of prior art in different languages and different technical fields.

  • International Preliminary Examination (optional)

One of the ISAs at your request carries out an additional patentability analysis, usually on a version of your application which you have amended in light of the content of the written opinion. The supplementary international search report is generally similar in content and appearance to the main international search report; it contains a listing of references to patent documents and other technical literature which may affect the patentability of the invention claimed in the international application. However, it does not repeat documents that have already been cited in the international search report, unless this is necessary because of new relevance when read in conjunction with other documents discovered during the supplementary international search. This Supplementary International Search Report has to be provided within 28 months from the filing of the local application.

  • National Phase

After the completion of 30/31 months, the PCT applicant enters the national phase. The applicant, after receiving the search report, can very well decide which country to file with, after the end of the international phase. The applicant has to fulfill some requirements which include paying national fees and, in some cases, filing translations of the application. These steps must be taken, concerning the majority of PCT Contracting States’ patent Offices, before the end of the 30th month from the filing date of local application.

It is difficult to have a general thought process when the PCT process is best.  Nevertheless, it can be fair to say that the PCT process is most popular and can be best suited for large multi-national corporations who regularly seek patents in many jurisdictions, such as Pharmaceutical companies. The PCT process is also advantageous when there is a clear global need and likely markets exist around the world. But it is imperative to take advice from a patent attorney while planning. 

Author: Saransh Chaturvedi (an advocate) currently pursuing LLM from Rajiv Gandhi School of Intellectual Property Law (IIT Kharagpur).  In case of any queries please contact/write back to us at

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