Anthropic says Claude Code source leaked by human error; removes 8,000 GitHub copies

Anthropic said part of Claude Code's internal source code was leaked by human error.

About 2,000 internal files and roughly 500,000 lines of code were exposed via an npm package update.

Anthropic used copyright takedown requests to remove over 8,000 reposted copies from GitHub by April 1, 2026.

The company stated the leak did not include secrets or credentials and called it a packaging mistake.