한국   대만   중국   일본 
International Patent Classification (IPC)
The Wayback Machine - https://web.archive.org/web/20070311065041/http://www.wipo.int:80/classifications/ipc/en/

International Patent Classification (IPC)

The Strasbourg Agreement (of 1971) concerning the International Patent Classification provides for a common classification for patents for invention including published patent applications, utility models and utility certificates. The International Patent Classification (IPC) is a hierarchical system in which the whole area of technology is divided into a range of sections, classes, subclasses and groups. This system is indispensable for the retrieval of patent documents in the search for establishing the novelty of an invention or determining the state of the art in a particular area of technology.

 

The Classification is periodically revised in order to improve the system and to take account of technical development. The current, eighth , edition of the IPC entered into force on January 1, 2006 .