Mozilla has finished work on version 2.0 of its Mozilla Public Licence, updating the agreement for the first time in more than a decade to fit better with other free software and open-source licences.
MPL 2.0, released on Tuesday by the Mozilla Foundation, is the result of 21 months of work on version 1.0, which was created in 1998 and revamped only once in 1999. It is a file-level copyleft licence designed to let developers share modifications of MPL-licensed code while incorporating code available under other open or proprietary licences.
"Version 2.0 is similar in spirit to the previous versions, but shorter, better, and more compatible with other free software and open-source licences," Mitchell Baker, chair of the Mozilla Foundation, said in a blog post.
The Mozilla Project, which uses the MPL to govern its Firefox browser and Thunderbird email client, has committed to moving to version 2.0. The revision has also been approved by the Free Software Foundation for GPL (GNU General Public License) compatibility and the Open Source Initiative as meeting free software and open-source standards.
Overall, the biggest change is the simplification of the terms of the MPL, the foundation said. For example, the terms no longer need to specify a time period for availability of source code; instead, the MPL only requires that the code must be available by the time the executable file is released.
The update adds features to bring the terms in line with the Apache licence, meaning code written under MPL 2.0 should be compatible with that agreement. It also allows software created under the MPL to be distributed alongside code licensed under the GPL or Lesser General Public License (LGPL).
In addition, the revamp provides the MPL with the same patent protections offered by other licences, "while also allowing any member of a community to defend a contributor who has been sued for infringement", the Mozilla Foundation said in its announcement.