Fossil

This difference in outlook allows a GPL-based project to do without a
[https://en.wikipedia.org/wiki/Contributor_License_Agreement|constributor
license agreement] (CLA) because by the very act of distributing
binaries, you are bound to also distribute the source under a compatible
license. There are GPL-based projects that do require a CLA, but this is
typically done in order to allow a corporation to "own" the
contributions so that it can legally relicense them to those who do not
wish to be subject to the GPL, usually for a hefty fee. A CLA is not
necessary for the legal integrity of a GPL-based
wish to be subject to the GPL. The GPL is being used in this case not so
much to promote the FOSS philosophy but as a prod to drive companies
toward the "commercial version," which is naturally available only for a
significant fee. Because a CLA is unnecessary for the legal integrity of
a GPL-based
[https://en.wikipedia.org/wiki/Free_and_open-source_software|FOSS]
project, so it's often dispensed with.
project, it's often dispensed with when there aren't other
considerations pushing the organization to require one.

Contrast a BSD-style project, where contributions are not automatically
relicensed merely by being distributed with the preexisting BSD code.
Such projects often require a CLA even when there is no corporate
overlord or commercial-use relicensing option. It is one way to ensure
that all contributions are compatibly licensed with the existing body of
code. It's a way to add a "no takebacks" clause to the basic BSD