In order to search patent applications and granted patents, some national or regional patent offices provide free-of charge electronic databases via Internet. A list of URLs of web-based databases is available:.
WIPO provides access to a comprehensive electronic database on published international patent applications filed under the PCT system from 1978 to the present day in image format and to fully searchable text of descriptions and claims for PCT International Applications filed as from July 1998.
Wherever web-based databases are not available, patent information may be consulted on paper, on microfilms or CD-ROMs, at the national or regional patent offices.
Searchable Internet patent databases have significantly facilitated the access to patent information. However, given the complexity of patent documents and the technical and legal skills required, it is advisable to contact a professional patent attorney if a high-quality patent search is required.
WIPO Patent Information Services (WPIS) provides free-of-charge services for users in developing countries who wish to obtain technical search results in relation to their inventions.