The developers of the Citadel messaging and collaboration system are pleased to announce that we are now releasing all of our software under version 3 of the GNU General Public License.
There has been an intentional effort by a particular producer of non-free software to subvert, erode, circumvent, and otherwise undermine the spirit of free software. In the light of recent events, it has become clear to us that GPLv3 will provide stronger protection from patent problems and license circumvention.
Citadel remains the only messaging and collaboration system offering end-to-end GPL across the entire code base, and we continue to lead in this area by being the first to adopt GPLv3. Furthermore, when compared with other systems in its category, Citadel remains the only one that is comprised of end-to-end free software at all. Others offer a feature-limited free version but require a paid license in order to use the “enterprise” or “network” edition. Citadel has no such limitation; we make our very best work available to everyone on the same terms.