The PCT us a patent treaty concluded in 1970, amended in 1979, and modified in 1984 and 2001. It is open to States party to the Paris Convention for the Protection of Industrial Property. Instruments of ratification or accession must be deposited with the Director General of WIPO. Nowadays PCT has 144 members.
The Treaty makes it possible to seek patent protection for an invention simultaneously in each of a large number of countries by filing an "international" patent application. Such an application may be filed by anyone who is a national or resident of a contracting state. It may generally be filed with the national patent office of the contracting state of which the applicant is a national or resident or, at the applicant's option, with the International Bureau of WIPO in Geneva.
The procedure under the PCT has the following advantages for the applicant:
- Presentation of a single "international" patent application in compliance with the formal requirements of the PCT, is made in one language and the payment of a single amount of fees.
- International Search where an International Searching Authority (ISA) analyzes the invention and provides an opinion on the potential patentability.
- International publication in which it is disclosed internationally the content of the international application, immediately after expiry of the period of 18 months from the earliest filing date (priority date).
- The office in charge of the "International Preliminary Examining" may perform at the request of the applicant, an additional patentability analysis, usually on a amended version of the application.
After the International Phase is finalized, the application enters into the national phase, requesting "the granting of the patent" in the National Patent Offices of the countries seeking protection.
The granting of patents remains a matter of national patent offices.