This website is an archive. It was used for drafting and public consultation on GPLv3 and version 3 of other GNU licenses which were published in 2007. For up to date information, see https://www.gnu.org/licenses/licenses.html. For more information about this archive, see https://www.fsf.org/licensing/gplv3-archive

From GPLv3 Wiki

This is a free software license but it is incompatible with version 2 of the GPL.

The Common Public License is incompatible with version 2 of the GPL because it has various specific requirements that are not in the GPL.

For example, it requires certain patent licenses be given that version 2 of the GPL does not require. (We don't think those patent license requirements are inherently a bad idea, but nonetheless they are incompatible with the GNU GPL version 2.)