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Creative Commons helps you share your knowledge and creativity with the world.

We're helping to realize the full potential of the Internet—universal access to research and education, full participation in culture—to drive a new era of development growth, and productivity.

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What is Creative Commons?

Creative Commons is a nonprofit organization that enables the sharing and use of creativity and knowledge through free legal tools.

Our free, easy-to-use copyright licenses provide a simple, standardized way to give the public permission to share and use your creative work — on conditions of your choice. CC licenses let you easily change your copyright terms from the default of “all rights reserved” to “some rights reserved.”

Creative Commons licenses are not an alternative to copyright. They work alongside copyright and enable you to modify your copyright terms to best suit your needs.

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https://creativecommons.org/compatiblelicenses

Compatible Licenses

This is the list of licenses that have been approved by Creative Commons as compatible with the two Creative Commons ShareAlike licenses, CC BY-SA and CC BY-NC-SA. You must use one of the licenses listed on this page for your contribution when you make adaptations of material under BY-SA or BY-NC-SA and share the adaptation, unless your use falls under an exception or limitation to copyright. Below is the definitive list of permissible licenses for your contributions to adaptations, which depends on the particular license that covers the material you are adapting.

Creative Commons evaluates licenses for ShareAlike compatibility according to its publishedprocess and criteria. Any license that has been considered formally by CC under this process will be listed on this page, with unsuccessful candidates noted in a separate section. To read about compatibility within the CC license suite, please see our FAQ.

BY-SA

See this page for an explanation of how compatibility with BY-SA works.

Version 4.0

Your contributions to adaptations of BY-SA 4.0 materials may only be licensed under:

BY-SA 4.0, or a later version of the BY-SA license.
Ported versions of the BY-SA license (if any), version 4.0 or later
A license designated as a “BY-SA Compatible License” as defined in BY-SA 4.0.
- Free Art License: The Free Art license 1.3 was declared a “BY-SA–Compatible License” for version 4.0 on 21 October 2014. See the full analysis and comparison for more information.
- GPLv3: The GNU General Public License version 3was declared a “BY-SA–Compatible License” for version 4.0 on 8 October 2015. Note that compatibility with the GPLv3 is one-way only, which means you may license your contributions to adaptations of BY-SA 4.0 materials under GPLv3, but you may not license your contributions to adaptations of GPLv3 projects under BY-SA 4.0. Other special considerations apply. See the full analysis and comparison for more information.

Other licenses may be added to this list at any time according to the established process and criteria. Once a license has been added to this list, it will not be removed.

Version 3.0

Your contributions to adaptations of BY-SA 3.0 materials may only be licensed under:

BY-SA 3.0, or a later version of the BY-SA license.
Ported versions of the BY-SA license, version 3.0 or later.
A license designated as a “Creative Commons Compatible License” as defined in BY-SA 3.0.

Currently, no non-CC licenses have been designated as compatible with BY-SA 3.0. Other licenses may be added to this list at any time according to the established process and criteria. Once a license has been added to this list, it will not be removed.

Version 2.0 and 2.5

Your contributions to adaptations of BY-SA 2.0 or 2.5 materials may only be licensed under:

The license used for the original work, or a later version of that BY-SA license.
Ported versions of that BY-SA license, the same or later version as the licensed work.

Version 1.0

There is no compatibility mechanism in CC BY-SA 1.0. You must use version 1.0 for your contributions to adaptations of material under BY-SA 1.0.

BY-NC-SA

Version 4.0

Your contributions to adaptations of material under BY-NC-SA 4.0 may only be licensed under:

BY-NC-SA 4.0, or a later version of the BY-NC-SA license.
Ported versions of the BY-NC-SA license, version 4.0 or later.
A license designated as a “BY-NC-SA Compatible License” as defined in BY-NC-SA 4.0.

Currently, no non-CC licenses have been designated as compatible with BY-NC-SA 4.0. Other licenses may be added to this list at any time according to the established process and criteria. Once a license has been added to this list, it will not be removed.

Versions 2.0, 2.5, and 3.0

Your contributions to adaptations of BY-NC-SA 2.0, 2.5 or 3.0 materials may only be licensed under:

The license used for the original work, or a later version of that BY-NC-SA license.
Ported versions of that BY-NC-SA license, the same or later version as the licensed work.

Version 1.0

There is no compatibility mechanism in CC BY-NC-SA 1.0. You must use version 1.0 for your contributions to adaptations of material under BY-NC-SA 1.0.