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
UnverifiedThe free software movement was launched by Richard Stallman in 1985, emphasizing the four freedoms to use, study, modify, and distribute software, and treating them as ethical and political issues.71% similarVerifiedRichard 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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