If Claude Code was predominantly written by Claude itself, does Anthropic even own it? That question stopped everyone from laughing on March 31, 2026. Anthropic had accidentally published 512,000 lines of Claude Code's source code. Within hours, a developer used AI to rewrite the entire thing in Python. The "claw-code" repository hit 100,000 GitHub stars in a day. Then Anthropic issued DMCA takedowns. For code that may not be copyrightable.
The US Copyright Office established in January 2025 that works predominantly generated by AI without "meaningful human authorship" get no copyright protection. The Supreme Court upheld this by declining the Thaler appeal in March 2026. Typing "build a rate limiter" and accepting what comes back probably doesn't qualify as meaningful. Substantially redirecting the output probably does. Between those extremes is where most developers live every day. Nobody has defined that space.
A San Francisco developer built a personal side project with code that was largely AI-generated. His employer claimed ownership. Their argument: the AI had visibility into work files, so anything it generated was a derivative work of company IP. Employment contracts with work-for-hire clauses already cover code built on company time, company machines, or with company-licensed tools. This developer's case stretched well beyond those boundaries. Legally shaky. Hasn't stopped them.
AI models train on GPL-licensed code. When they output something that closely resembles that training data, you may have imported copyleft obligations into your proprietary codebase without knowing. In the chardet dispute earlier in 2026, a developer used Claude to rewrite an LGPL-licensed library and re-released it under MIT, calling it a clean-room implementation. Sena Evren at Legal Layer sees this as a preview. Tools like FOSSA and Snyk can scan for these issues. Most developers shipping AI-generated code aren't checking.
Claude can generate complex software systems with little human intervention, raising further questions about ownership and authorship.