Effective today, all Subscriber Content on Stack Overflow and the Stack Exchange network will be available under the terms of version 4.0 of the Creative Commons Attribution-ShareAlike (CC BY-SA) license.

This change follows our last Terms Of Service (ToS) update where we inadvertently introduced a point of confusion: the new ToS links to version 4.0 of the CC BY-SA license in support of defining the use of a Creative Commons license, where the previous terms linked to version 3.0 of the license. That’s not a problem itself, but the footer section of our websites continued to specify version 3.0 of the CC BY-SA license; this was an oversight.

It was our intention to update the footer information in a manner that was commensurate with the updated terms. We'd like to thank those from our communities that thoughtfully pointed out the issue and we have subsequently improved our review process.

Today's change will bring things into alignment by updating the information in the footer and we will continue forward under version 4.0 of the CC BY-SA license. This change encompasses all Subscriber Content as described in our ToS including data dumps as well as any content previously made available by Stack Exchange under the terms of version 3.0 of the CC BY-SA license.

If you have any questions about how licenses may or may not impact your business or personal projects, it's better to speak with your own attorney — we can't provide advice specific enough to be of much use in most cases.

4.0 has many advantages, and we encourage you to read the announcement letting the world know it was ready as a starting point if you're curious about the improvements.

We're happy to hear any thoughts about this, particularly from those in our international communities. If you've got questions pertaining to the change, we'll do our best to answer them, as long as we can answer without giving specific advice.

Effective today, all Subscriber Content on Stack Overflow and the Stack Exchange network will be available under the terms of version 4.0 of the Creative Commons Attribution-ShareAlike (CC BY-SA) license.

This change follows our last Terms Of Service (ToS) update where we inadvertently introduced a point of confusion: the new ToS links to version 4.0 of the CC BY-SA license in support of defining the use of a Creative Commons license, where the previous terms linked to version 3.0 of the license. That’s not a problem itself, but the footer section of our websites continued to specify version 3.0 of the CC BY-SA license; this was an oversight.

It was our intention to update the footer information in a manner that was commensurate with the updated terms. We'd like to thank those from our communities that thoughtfully pointed out the issue and we have subsequently improved our review process.

Today's change will bring things into alignment by updating the information in the footer and we will continue forward under version 4.0 of the CC BY-SA license. This change encompasses all Subscriber Content as described in our ToS including data dumps as well as any content previously made available by Stack Exchange under the terms of version 3.0 of the CC BY-SA license.

If you have any questions about how licenses may or may not impact your business or personal projects, it's better to speak with your own attorney — we can't provide advice specific enough to be of much use in most cases.

4.0 has many advantages, and we encourage you to read the announcement letting the world know it was ready as a starting point if you're curious about the improvements.

We're happy to hear any thoughts about this, particularly from those in our international communities. If you've got questions pertaining to the change, we'll do our best to answer them, as long as we can answer without giving specific advice.

Update: Please read our update on Creative Commons Licensing for more follow up on issues that stemmed from the change in license described above.