International Patent

The PCT does not make any specific provision concerning the types of invention, which may be the subject of an international application. Rules 39 and 67 permit International Searching and Preliminary Examining Authorities not to carry out search and examination on certain types of subject matter, such as scientific and mathematical theories, methods of doing business and computer programs to the extent that the Authority is not equipped to carry out a search or international preliminary examination concerning such programs. However, while a lack of international search may make national processing more difficult, Article 27(5) PCT makes clear that this does not affect the issue of whether the invention is patentable under the laws of the designated States.

The first step of the procedure consists in filing an international (patent) application with a suitable patent office, called a Receiving Office (RO). This application is usually called an international application or simply a PCT application since it does not result in an international patent nor in a PCT patent (both of which do not exist). The international application needs to be filed in one language only (though translations may still be required for international search and international publication, depending on the language of filing and the International Searching Authority to be used). At least one applicant must be a national or resident of a Contracting State to the PCT, otherwise no international filing date is accorded. In most member states, the applicant or at least one of the applicants of the application is required to be a national or resident of the state of the receiving office where the application is filed. Applicants from any contracting state may file an international patent application at the International Bureau in Geneva

The Patent Cooperation Treaty (PCT) is an international patent law treaty, concluded in 1970. It provides a unified procedure for filing patent applications to protect inventions in each of its Contracting States. A patent application filed under the PCT is called an international patent application.

The States party to the PCT, i.e. the Contracting States, constitute the International Patent Cooperation Union. Upon filing the international application, all Contracting States are automatically designated. An international patent application has the same standing during the international phase as if a national or regional patent application had been filed in every contracting state of the PCT.

"Nothing in this Treaty and the Regulations is intended to be construed as prescribing anything that would limit the freedom of each Contracting State to prescribe such substantive conditions of patentability as it desires. (...)"

A single filing of an international application is made with a Receiving Office (RO) in one language. It then results in a search performed by an International Searching Authority (ISA), accompanied with a written opinion regarding the patentability of the invention which is the subject of the application. It is optionally followed by a preliminary examination, performed by an International Preliminary Examining Authority (IPEA). Finally, the examination (if provided by national law) and grant procedures are handled by the relevant national or regional authorities. The PCT does not lead to the grant of an "international patent", which does not exist.