Anthropic is in advanced talks to acquire Stainless, a four-year-old New York developer tools startup, for at least $300M, marking a significant premium to its last valuation of $150M in December 2024. Stainless sells software that takes complicated APIs and uses AI to automatically generate software development kits that make it easier for developers, non-technical people, and AI agents to build applications from those APIs, with customers including Anthropic, OpenAI, and Google, as well as non-model companies like Cloudflare and Cerebras. If the deal closes, Anthropic would own a main way developers access OpenAI and Google models, and the acquisition would extend Anthropic's recent dealmaking streak following the company's acquisitions of developer tools startup Bun in December, computer use startup Vercept, and AI biotech startup Coefficient Bio.
