List the recent purchase they have made and what they hoped to buy with each purchase.
Anthropic made four acquisitions in six months — Bun, Vercept, Coefficient Bio, and Stainless — each targeting a different layer of the software stack Claude needs to act in the wider world.
Why it matters: The buying spree is a bet that owning the infrastructure layer — from JavaScript runtimes to SDK generators — gives Claude a structural edge that model quality alone can't deliver.
- Bun (Dec 2025, undisclosed price): the fast JavaScript runtime — Anthropic wanted the developer-side execution layer for AI coding agents.
- Vercept (Feb 2026, undisclosed price): an AI computer-use startup — Anthropic wanted to give Claude the ability to see and operate desktop software, not just generate text.
- Coefficient Bio (Apr 2026, ~$400M in stock): a stealth biotech AI startup backed by Dimension — Anthropic wanted former Genentech researchers and drug-discovery capability to anchor a life sciences vertical.
- Stainless (May 2026, $300M+): the SDK generator used by OpenAI, Google, Meta, and Cloudflare — Anthropic wanted the tooling layer that connects any AI model to outside software, and is shutting the shared service down.
- The Stainless shutdown is contested in the developer community: critics argue Anthropic is deliberately degrading a neutral tool to handicap OpenAI and Google, while Anthropic frames it as consolidating developer tooling around Claude — the same facts, opposite interpretations of intent.
