Recommended copyleft licenses
This page is maintained by the Free Software Foundation's Licensing and Compliance Lab. You can support our efforts by making a donation to the FSF. Have a question not answered here? Check out some of our other licensing resources or contact the Compliance Lab at licensing@fsf.org.
This page lists the copyleft licenses that we recommend free software projects and associated documentation use.
Software licenses
- The GNU General Public License, version 3 or any later version
- The GNU Affero General Public License, version 3 or any later version
Documentation licenses
- The GNU Free Documentation License, version 1.3 or any later version
To learn more about when and why we recommend these licenses, please see How to choose a license for your own work. Note that only the licenses listed above are recommended copyleft licenses; other licenses discussed in that guide are not copyleft licenses, or else suggested for use in more narrow circumstances.