Claude writes 90% of code at Anthropic, IPO filing shows
Anthropic's IPO filing reveals its AI model Claude wrote over 90% of the company's codebase contributions in September, with engineers now directing and reviewing AI output rather than writing code line by line. The October 26 S-1 filing for a Nasdaq listing under "ANT" shows daily code contributions per engineer rose over 45 times from 2024 levels. Anthropic's workforce grew from about 940 to 5,300 employees, with the company relying on Claude to research, design, and develop future models. CEO Dario Amodei predicted this milestone in March 2025, and some teams report engineers no longer writing code by hand. The filing warns of risks from AI systems behaving in unintended ways, despite their central role in operations.