On Sunday, January 27, 2019 06:47:05 AM Ben Finney wrote: > Howdy all, > > Recently in this forum, some concerns have been raised about works > covered by GNU GPL. In particular, whether a recipient of a work, > received under conditions of the GNU GPL, can have the freedoms of the > GNU GPL later withdrawn in that same work. > > To reassure those who might worry whether they can reply on the freedom > granted in a work, it is worth reading the GNU FAQ document for the GNU > GPL at the Free Software Foundation: > > [For any GNU GPL-licensed work,] the public already has the right to > use the program under the GPL, and this right cannot be withdrawn. > > > <URL:https://www.gnu.org/licenses/gpl-faq.en.html#CanDeveloperThirdParty> > > The same answer is in the FAQ specifically for the GNU GPL version 2.0 > <URL:https://www.gnu.org/licenses/old-licenses/gpl-2.0-faq.html#CanDevelope > rThirdParty>. > > You can read more in the Software Freedom Conservancy's document > _Copyleft and the GNU General Public License: A Comprehensive Tutorial > and Guide_, specifically in §7.4 “GPLv2 Irrevocability”. That concludes: > > Whether as a matter of a straightforward contractual obligation, or > as a matter of promissory estoppel, a contributor’s attempt to > revoke a copyright license grant and then enforce their copyright > against a user is highly unlikely to succeed. > > > <URL:https://copyleft.org/guide/comprehensive-gpl-guidech8.html#x11-540007 > .4> > > In other words: Any copyright holder can *say* they wish to > retroactively revoke the GNU GPL to some party. However, unless that > party has violated the conditions of the GNU GPL grant they originally > received, there does not appear to be any enforcible threat of > revocation that would succeed. > > I hope these, along with the many court cases world-wide that have > tested the GNU GPL and found it to be enforcible, can reassure those > considering whether a particular copyright holder's whim can revoke the > freedoms guaranteed in a GNU GPL-covered work. I'd say there's nothing > to worry about from those threats.
I don't disagree with what is stated here (but I have a headache and didn't read it carefully), but, even without reading carefully, I believe that the original author of a package could do something like create further modifications to the code and create a non-free version of the code. Assuming that is correct, people using (or basing modifications) on the (presumably) older free version could continue to use and develop based on that, but would not have rights to that new non-free version.
