You need to distinguish past and future releases.
True, the copyright holder can do nothing whatsoever about the code that's already out there.
But as the FSF has the copyright on the whole code, the only thing that'd prevent it from releasing proprietarylibc tomorrow is their promise not to do that, which they gave by way of their past policies and activities.
Other organizations which required copyright assignment either never did so (Canonical) or even explicitly state that there's a commercial version (mysql).
Posted Mar 31, 2012 19:28 UTC (Sat) by giraffedata (subscriber, #1954)
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You need to distinguish past and future releases.
The distinction is not between past and future releases, but between the code and the project. GPL's provision for forking means the distributor can't control future releases, because anyone can make one. And that's central to GPL's purpose.
But GPL isn't meant to give the public control of a project such as the GNU libc project, and that control is what the copyright assignment is designed to prevent.
Planning for decades
Posted Apr 5, 2012 20:02 UTC (Thu) by Wol (guest, #4433)
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Actually, I believe there IS something that would stop them releasing proprietarylibc.
It's called a contract.
aiui, the standard contract assigning copyright to the FSF places some restrictions on what they can do, and that's one of them.