The Python library chardet, used by the popular requests package, has been relicensed from LGPL to MIT via an AI-assisted rewrite using Claude Code. This move has ignited a fierce debate within the open source community. The original author, a2mark, argues this constitutes a GPL violation because the AI-generated code is a derivative work of the LGPL-licensed Mozilla C++ code, bypassing the traditional 'clean room' rewrite requirement that separates teams to avoid copyright infringement. The legal complexity is amplified by a recent U.S. Supreme Court decision upholding a 'Human Authorship' requirement for copyright, creating a paradox: if AI output lacks copyright, the maintainers may lack standing to license v7.0.0, yet if it's a derivative, the relicensing is invalid.

This case represents a critical test for AI's role in open source relicensing. Accepting AI rewrites as a valid relicensing method could fundamentally undermine Copyleft licenses like GPL, allowing developers to take any GPL project, feed it to an LLM, and release it under MIT. The chardet maintainers argue the AI output is a new work, but the Supreme Court's stance and the original author's objections highlight the unresolved legal boundaries. The outcome of this dispute will significantly shape the future of AI-assisted development and open source licensing.

The controversy centers on whether the AI-generated code constitutes a derivative work of the original LGPL code. If the AI 'learned' from the LGPL code, the resulting output inherits copyright status, potentially requiring LGPL compliance. Conversely, if the AI output is deemed a completely new creation, the original license might not apply, but the Supreme Court's 'Human Authorship' ruling complicates this. The case underscores the urgent need for clearer legal frameworks governing AI's use in modifying open source software and the potential end of the Copyleft model if AI rewriting becomes standard practice.