# Why Didn't Anthropic Sign the Open Model Letter? AI Offense Outpaces Defense

> Source: <https://uk.pcmag.com/ai/166418/why-didnt-anthropic-sign-the-open-model-letter-ai-offense-outpaces-defense>
> Published: 2026-07-28 17:42:41+00:00

An open letter [urging](https://uk.pcmag.com/ai/166349/in-face-of-us-crackdown-microsoft-nvidia-ceos-back-open-weight-ai-models) the US to support rather than restrict open-weight AI models has received public support from all the major tech companies—except Anthropic. CEO Dario Amodei is now explaining why, suggesting that open AI models could empower attackers more than defenders.

Amodei says he …