Anthropic has confirmed that the Claude Code source code was accidentally leaked by an employee. In an incident that happened yesterday, 1,900 TypeScript files with over 500,000 lines of code were leaked exposing several internal libraries, features in development, and tools Anthropic uses to train Claude Code.
The incident occurred due to negligence and not because they were hacked or an act of internal sabotage. The files were then quickly downloaded before being re-uploaded to the Github site. After Anthropic realized what had happened, they issued a takedown notice of the shared file using copyright law. In a short time, the file was shared 41,000 times.
After successfully deleting it on Github, the file is now being shared on third-party sharing sites and all efforts to permanently delete it are now too late. At first, many did not believe the source code leak because it happened at 4am on April 1st and thought it was just an April Fool's joke by Anthropic.
Anthropic also said that only source code was leaked but no sensitive customer data was involved or exposed. They are implementing measures to prevent this from happening again.
