GPL doesn&#x27;t even protect against this kind of situation. The copyright holder is not bound by the GPL license, they are the one licensing it. Anything release under the GPL is still available as GPL, but the copyright holder has no obligation to release future changes under the GPL. They can instead have a proprietary license. Things can get a little more muddied with community contributions as the contributor owns the copyright to the change, unless they sign over the copyright as part of a contributor agreement.