World Intellectual Property Organization

Summary of the Strasbourg Agreement Concerning the International Patent Classification (1971)

The Strasbourg Agreement establishes the International Patent Classification (IPC) which divides technology into eight sections with approximately 70,000 subdivisions. Each subdivision is denoted by a symbol consisting of Arabic numerals and letters of the Latin alphabet.

The appropriate IPC symbols are indicated on patent documents (published patent applications and granted patents), of which over 2 million are issued each year. The appropriate symbols are allotted by the national or regional industrial property office that publishes the patent document. For PCT applications, IPC symbols are allotted by the International Searching Authority.

Classification is indispensable for the retrieval of patent documents in the search for "prior art". Such retrieval is needed by patent-issuing authorities, potential inventors, research and development units and others concerned with the application or development of technology.

Although only 62 States are party to the Agreement, the IPC is used by the patent offices of more than 100 States, four regional offices and the Secretariat of WIPO in administering the Patent Cooperation Treaty (PCT) (1970).

In order to keep the IPC up to date, it is continuously revised and a new edition is published each year on January 1.

The revision of the IPC is carried out by the IPC Committee of Experts set up under the Agreement. All States party to the Agreement are members of the Committee of Experts.

The Strasbourg Agreement created a Union, which has an Assembly. Every State that is a member of the Union is a member of the Assembly. Among the most important tasks of the Assembly is the adoption of the biennial program and budget of the Union.

The Agreement – commonly referred to as the IPC Agreement – was concluded in 1971 and amended in 1979. It is open to States party to the Paris Convention for the Protection of Industrial Property (1883). Instruments of ratification or accession must be deposited with the Director General of WIPO.

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