I don't think I can give any "official" source, but I think this post explains it fairly well:
> > The copyright holder (or, more commonly, holders) can release a version of the software that uses a totally different license. Everyone who uses earlier versions of the software can continue to use it under the terms and conditions of the previous license, but from that new version forward the new license applies to anyone who uses the software.
> >
> > [...]
> >
> > It requires getting the copyright holders to agree that their contributions can be released under the new license, and for some projects that can mean tracking down hundreds or thousands of individuals. However for other projects—especially projects with a primary corporate sponsor or those with a Contributor License Agreement that includes copyright assignment—there typically are considerably fewer copyright holders, making the overall relicensing process much easier.
https://anonymoushash.vmbrasseur.com/2022/10/27/open-source-relicensing-business-risk
They name several examples, all of which are relicensed from permissive licenses.
I looked at that person's [resume](https://www.vmbrasseur.com/resume.pdf ), which states that they were previously a member of SPDX Legal Project
TheEvilSkeleton
npub1gc…el3rh
2024-08-20 12:03:02 UTC
in reply to nevent1q…jlf3
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npub1gcf8zwxgqpnl08gwnancjvvv0pggt5wgpphtjxpgrtzsz0tf6f6s4el3rhSeen on
wss://relay.momostr.pinkPublished at
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"content": "I don't think I can give any \"official\" source, but I think this post explains it fairly well:\n\n\u003e \u003e The copyright holder (or, more commonly, holders) can release a version of the software that uses a totally different license. Everyone who uses earlier versions of the software can continue to use it under the terms and conditions of the previous license, but from that new version forward the new license applies to anyone who uses the software.\n\u003e \u003e\n\u003e \u003e [...]\n\u003e \u003e\n\u003e \u003e It requires getting the copyright holders to agree that their contributions can be released under the new license, and for some projects that can mean tracking down hundreds or thousands of individuals. However for other projects—especially projects with a primary corporate sponsor or those with a Contributor License Agreement that includes copyright assignment—there typically are considerably fewer copyright holders, making the overall relicensing process much easier.\n\nhttps://anonymoushash.vmbrasseur.com/2022/10/27/open-source-relicensing-business-risk\n\nThey name several examples, all of which are relicensed from permissive licenses.\n\nI looked at that person's [resume](https://www.vmbrasseur.com/resume.pdf ), which states that they were previously a member of SPDX Legal Project",
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