This stackoverflow question have some good points (notably, the accepted answer, and the bit about limitations - the CDDL section 6.2, for example revokes the C

This stackoverflow question have some good points (notably, the accepted answer, and the bit about limitations - the CDDL section 6.2, for example revokes the CDDL in case of patent infringement, something that might be considered an "extra limitation" under the GPL (you're not allowed to add additional limitations to either the GPL or the CDDL). As such, the CDDL might be incompatible with the GPL up to and including v2 - while GPL3 might also be incompatible with the CDDL): https://opensource.stackexchange.com/questions/2094/are-cddl-and-gpl-really-incompatible https://opensource.stackexchange.com/questions/2094/are-cddl... https://github.com/zfsonlinux/zfs/blob/master/OPENSOLARIS.LICENSE https://github.com/zfsonlinux/zfs/blob/master/OPENSOLARIS.LI... Also, the SO answer mentions consumer protection laws - but AFAIK they generally only apply to consumers - not businesses. So the GPL 0 clause might be void in many jurisdictions for individuals but still valid for businesses.