Verified65% confidenceFactExact time
The copyleft mechanism was advocated by Richard Stallman in the free software movement.
3
Sources
65%
Confidence
Long-term
Relevance
8/4/2026
First Seen
Sources
MIT许可证能用于闭源代码吗？完整解析
Related Claims
VerifiedRichard Stallman launched the GNU project in the 1980s and regarded documentation freedom as equally important as code freedom.70% similarUnverifiedCopyleft is a core legal mechanism proposed by Richard Stallman in the GNU project, requiring that derivative works be released under the same or a compatible license.66% similarUnverified1983年Richard Stallman发起GNU项目，并创立GPL许可证用版权法保障软件自由62% similarVerifiedRichard Stallman launched the GNU project in 1983.61% similar
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