A summary of the licensing situation unfolding at chardet, its ties with AI and its ramifications for open-source.

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A controversy has erupted around chardet, a widely used Python character encoding library. Its maintainer Dan Blanchard released version 7.0.0 as an alleged complete rewrite, relicensing it from LGPL 2.1 to MIT. Original author Mark Pilgrim argues this relicensing is illegal under LGPL, which requires derivative works to remain under the same license. The maintainer claims it qualifies as a 'clean room' rewrite because it was AI-generated (using Claude) from a high-level description — but evidence shows the AI was explicitly instructed to reference chardet 6.0.0's source files, undermining that claim. The situation raises broader questions about whether AI-assisted rewrites can be used to circumvent copyleft licenses, the copyrightability of AI-generated code, and what precedent this sets for open-source licensing if such relicensing is allowed to stand.

On chardet, AI and OSS licensing