A month ago we proposed new licensing terms to cover code posted at Stack Overflow and across the Stack Exchange network. The voting on to the proposal was highly positive, but many of you let us know we can do even better. We considered all your feedback, and after careful consideration we have modified the proposal.
- Attribution will be required when you use code found at Stack Overflow and Stack Exchange
- The changes will now go into effect March 1, 2016
Change 1 was made to accommodate contributors who want credit, plus to help developers identify the provenance of a Stack Overflow code snippet when they find it integrated into a project. Change 2 was made to allow you more time to digest this change and socialize it within your organizations.
Both changes were thoroughly vetted internally, with our lawyers, and with the OSI. We think they are an improvement upon the previous proposal, and a vast improvement upon the status quo.
As always, community input has been instrumental in moving this initative forward. We're fairly certain we've arrived at the best possible balance for everyone's needs, but if you spot anything new you think we've missed, please let us know.
The Fine Print:
Starting March 1, 2016, new contributions across the network will be licensed to the public under the following terms:
- Non-code contributions will continue to be available for use under the terms of CC-BY-SA
- Code contributions will be available for use under the terms of the MIT License
- You don’t have to include the full MIT License in your code base. Contributors agree to give code users permission to ignore the MIT License’s notice preservation requirement, as long as users give reasonable attribution. This optional exception to the MIT License will live in our terms of service.
The only difference between the terms described above and the previous proposal is the removal of the requirement to add attribution only “upon request of the copyright holder (or Stack Exchange on behalf of the copyright holder)”. “Reasonable attribution” is now required by end users of Stack Overflow and Stack Exchange.
What is reasonable attribution?
A URL as a comment in your code is reasonable attribution.
There are certainly other forms of reasonable attribution, depending on use, and you are welcome to go above and beyond what’s required and include username, date, and anything else if you like.
You are also welcome to use the MIT License as it is traditionally interpreted: by preserving the full license with relevant fields (copyright year and copyright holder) completed.
Full guidance will be provided in an upcoming FAQ.
When will the new terms go into effect?
March 1, 2016
What about other sites on the Stack Exchange network?
The new terms will go into effect for all new code on all sites in the Stack Exchange network.
We understand that some users feel the new terms are not a perfect fit for certain sites, but we think fragmenting the license across the network will lead to ambiguity – the exact problem we’re trying to solve by updating the terms.
What about code contributed prior to March 1, 2016?
This change is just a first step in establishing clarity for using code found on Stack Overflow and Stack Exchange. Code contributed prior to March 1 will be available for use as it has always been. We are exploring ways we might distinguish code covered by each license regime, and we hope to soon roll out an opt-in mechanism to let users relicense their old contributions under the new terms.
But what is code?
We will give you guidance on identifying code in an upcoming FAQ, plus guidance on how best to comply with the attribution requirement. But ultimately, identifying code will be a judgement call on your part. We have full faith in your ability to do this.
We want to hear what you think. Barring any showstopper, these terms and a detailed FAQ will be rolled out March 1, 2016.