Rescinding licenses

[Wuzzy]

What happens if a contributor to $WELL_KNOWN_FREE_SOFTWARE suddenly says: “I rescind all my contributions to $WELL_KNOWN_FREE_SOFTWARE, I revoke the license I have released my contributions under and I demand that all my contributions be removed from it!.”?
Can the contributor really recind the contributions? Does the project have to obey with the demand, or can they keep them legally?

What happens if the only author of $LITTLE_KNOWN_FREE_SOFTWARE suddenly says “I recind my license of my software, it is now released under $SHITTY_EULA, effective immediately.”?
What happens to existing users, who have downloaded the software already, where the software was still free (let's assume the software had a LICENSE file with a free license inside). Do they get to keep using the software under the old license, or do they lose their freedoms? And what about old versions? Can the author recind the license for already published versions retroactively?

Please, before you reply, also specify:
- To which country your answer applies
- Your sources

These sound like difficult but important questions to me. If you have any ideas, I would be very thankful for an answer.

[Lyberta]

From GPLv3:

2. Basic Permissions.

All rights granted under this License are granted for the term of
copyright on the Program, and are irrevocable provided the stated
conditions are met.

I'm pretty sure all common FOSS licenses are irrevocable.

[anon666]

i don't have sources (mostly since most of the licensing stuff i know i know for a long time),
but its actually pretty clear:
the license applies on "per-release" basis (or per-time period), thus the author can close his future work if he wants (or even if its a fork, they can chose to close any further work), but any previous work (and each release of it) will stay free and under the same license or can be forked if needed (say under compatible license)

think of software releases as of physical releases = nobody can take it back because its already yours (or belong to community)

[anon666]

tldr if it was ONCE under say GPL it will be forever under GPL (the release, even if it was only once)

[ffaf]

the license applies on "per-release" basis (or per-time period), thus the author can close his future work if he wants (or even if its a fork, they can chose to close any further work), but any previous work (and each release of it) will stay free and under the same license or can be forked if needed (say under compatible license)

What you say is right but just to make it extra clear for OP: of course if the licence is copyleft and you are not the sole copyright owner (e.g. 99% of multicontributor repos), you cannot close further work (or rather, you can but you cannot release anything).

[Technopeasant]

I mean, this is why we still have variants of Tux Racer or Nexuiz, so...

[Ntech]

Yea, most FOSS licenses include an irrevocable clause. Moreover, once rights are granted, they may not be rescinded unless such a clause exists in the license.

[Wuzzy]

That's a HUGE relief. So it's impossible that one disgruntled ex-contributor of an important subsystem can just say “I'm rescinding my license” and create a whole mess in FOSS.

The people who wrote the licenses are not dumb.

[JeffM2501]

Yes, the author of that sub system may choose to make future versions of the subsystem be under a different license, but you will always have access and rights to the version you used under the open source license that was in place when you got the code. This situation does happen and one of the ways how forks happen. If the author decided to add new features to a new version of the library and make that closed source, they have full rights to do that since they are the copyright holder. You would still have rights to use the last version that was released under the open source license (without the new features and changes of course), and in the future you'd be responsible for maintaining your own changes to the codebase under that open source license.

The irrevocable clause is one of the factors that makes a license truly open source. So anything under a common open source license, GPL, LGPL, MIT, etc... will not have a problem.

[Jastiv]

The fact that open source licenses are irrevocable is what makes them so useful. So even if you yourself get some bad idea to close the source code in the future, because, money or something, you can't take the code back from the community.