Anthropic accidentally exposed part of Claude Code's internal source code

The leak comes after Anthropic saw a surge of downloads over the past month. Bloomberg/Getty Images 2026-04-01T03:22:06.417Z Share Copy link Email Facebook WhatsApp X LinkedIn Bluesky Threads lighning bolt icon An icon in the shape of a lightning bolt.

Impact Link Save Saved Read in app This story is available exclusively to Business Insider subscribers. Become an Insider and start reading now. Have an account? Log in. Anthropic accidentally leaked some source code for Claude Code, its AI-powered coding assistant. The company said the leak did not include sensitive customer data or credentials. Anthropic recently experienced a surge in downloads following its split from the Pentagon. AI-generated summary Summaries are generated by an AI model trained on Business Insider's articles. AI may make mistakes or provide inaccurate/incomplete information. We're unable to load that answer right now. Please try again. What is Claude Code? Why did Anthropic split from the Pentagon? How is AI safety ensured during releases? How do leaks impact AI companies? What are the risks of source code leaks? Rival developers just gained insight into how Anthropic built its popular AI-powered coding assistant tool, Claude Code. Loading audio narration... The company accidentally leaked part of the internal source code for Claude Code during a release, a spokesperson confirmed to Business Insider on Tuesday."Earlier today, a Claude Code release included some internal source code. No sensitive customer data or credentials were involved or exposed," an Anthropic spokesperson said in a statement. "This was a release packaging issue caused by human error, not a security breach. We're rolling out measures to prevent this from happening again."An X post with a link and a screenshot of what appeared to be internal source code for Claude Code had racked up 26 million views on X as of Tuesday evening.The exposed code was related to Claude Code itself, not the underlying AI models.The leak could give a leg up to Anthropic's rivals by offering an inside look into one of its most popular products. It also raises security questions about a company that has positioned itself as focused on AI safety.The leak comes after a period of growth for Anthropic, fueled by a very public breakup with the Pentagon in February. After CEO Dario Amodei refused to back down in a dispute over how its AI could be used, the Defense Department instead struck a deal with OpenAI.Last week, a US District Judge Rita Lin granted a temporary injunction blocking the supply chain risk designation.Following the dispute, Anthropic's Claude chatbot saw a surge of downloads over the past month, briefly rising to No. 1 in the US Apple App Store.