4. Simon Willison: Can Coding Agents Relicense Open Source Through "Clean Room" Rewrites?
simonwillison.net·high signal
Willison analyzes the chardet library case where a maintainer used Claude Code to rewrite LGPL code under MIT, claiming a "clean room" approach. Original author Mark Pilgrim disputes this, arguing the maintainer's decade of exposure to the original code and Claude's training data contamination invalidate the claim. Willison raises fundamental questions: Can models trained on codebases produce defensible clean-room implementations? Could cheaper code generation enable wholesale relicensing of mat