From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Patentleft (also patent left, copyleft-style patent license or open patent) is the practice of licensing patents (especially biological patents) for royalty-free use, on the condition that adopters license related improvements they develop under the same terms. Copyleft-style licensors seek "continuous growth of a universally accessible technology commons" from which they, and others, will benefit.[1][2]

Patentleft is analogous to copyleft, a license which allows distribution of a copyrighted work and derived works, but only under the same terms.


The Biological Innovation for Open Society (BiOS) project implemented a patentleft system to encourage re-contribution and collaborative innovation of their technology. BiOS holds a patented technology for transferring genes in plants, and licenses the technology under the terms that, if a license holder improves the gene transfer tool and patents the improvement, then their improvement must be made available to all the other license holders.[3]

The open patent idea is designed to be practiced by consortia of research-oriented companies[4] and increasingly by standards bodies. These also commonly use open trademark methods to ensure some compliance with a suite of compatibility tests, e.g. Java, X/Open both of which forbid use of the mark by the non-compliant.[citation needed]

On October 12, 2001 the Free Software Foundation and Finite State Machine Labs Inc. (FSMLabs) announced a GPL - compliant open-patent license for FSMLabs' software patent, US 5995745 . Titled the Open RTLinux patent license Version 2, it provides for usage of this patent in accordance with the GPL.[5]


Person A has a patent, and licenses it under a patentleft license.

Person B has two patents in her product and wants to use Person A's patents in that product. Person B also wants to charge royalties for her two patents. She decides to use Person A's patent, but now must license her patents, royalty-free, under the same terms as Person A's patent.

Person C has three patents in his product and wants to use Person B's two patents in that product, but doesn't want to use Person A's patent. Person C also wants to charge royalties for his three patents. He decides to use Person B's patent, but now must license his patents, royalty-free, under the same terms as Person A's patent.

See also[edit]


Further reading[edit]

External links[edit]


None of the audio/visual content is hosted on this site. All media is embedded from other sites such as GoogleVideo, Wikipedia, YouTube etc. Therefore, this site has no control over the copyright issues of the streaming media.

All issues concerning copyright violations should be aimed at the sites hosting the material. This site does not host any of the streaming media and the owner has not uploaded any of the material to the video hosting servers. Anyone can find the same content on Google Video or YouTube by themselves.

The owner of this site cannot know which documentaries are in public domain, which has been uploaded to e.g. YouTube by the owner and which has been uploaded without permission. The copyright owner must contact the source if he wants his material off the Internet completely.

Powered by YouTube
Wikipedia content is licensed under the GFDL and (CC) license