Some important changes have occurred in the latest releases of several jQuery projects such as core, UI, Mobile, Sizzle, and QUnit. You may not have noticed them because they didn’t really change the actual code, documentation, or functionality. Instead, these changes were designed to clarify the ownership and licensing of the software. If you’re not a lawyer, most of this won’t make a lot of difference to you, but it’s important to us.
One simplification we made was to remove the GNU General Public License (GPL), leaving only the MIT License. Having just one license option makes things easier for the Foundation to manage and eliminates confusion that existed about the Foundation’s previous dual-licensing policy. However, this doesn’t affect your ability to use any of the Foundation’s projects. You are still free to take a jQuery Foundation project, make changes, and re-license it under the GPL if your situation makes that desirable. The Free Software Foundation site confirms that the MIT License is a “lax, permissive non-copyleft free software license, compatible with the GNU GPL.”
Over time, more than 500 people have contributed to the projects currently managed by the jQuery Foundation. We’re working hard to make sure that everyone who has contributed gets the credit they deserve. Many of the projects now have an AUTHORS.txt file in their root that list all the major contributors in chronological order. Scott González did a lot of the heavy lifting to get the author lists in order, and created useful tools so that we can keep them that way. Of course, you can always see the author of a specific change to a project by looking at the commit in the git log or on GitHub.
It’s important to the jQuery Foundation that licensing of the code and documentation is clear, so the community can continue to use it without interruption. Doing so requires a “paper trail” so it is unambiguous that the Foundation has permission to use the code and the contributor had the ability to contribute that code in the first place. For an example of the latter, think about the situation where an employee works on jQuery Foundation projects at the company office; their employer might claim they own that work and the employee had no right to license it to the Foundation.
To make the licensing clear, contributors are asked to sign a Contributor License Agreement (CLA). jQuery team members will sign a Copyright Assignment Agreement (CAA) which actually assigns the copyright to the jQuery Foundation. For more discussion of what a CLA or CAA does, see this article.
All of these changes guarantee that the jQuery Foundation’s open source projects will be dependable resources for developers and businesses. They also ensure that when you contribute, you’ll get some recognition for the work that you’ve done. So with all that legal stuff out of the way, come help us build the jQuery Foundation projects!