Anthropic and OpenAI skipped the open-weights letter

Twenty-five organizations signed a statement on Friday titled “Open Weights and American AI Leadership,” warning Washington against “premature restrictions” on open weights. Signatories include Microsoft, Nvidia, Meta, Hugging Face, IBM, Mozilla, Palantir, Perplexity, Mistral, and Y Combinator. Anthropic and OpenAI didn’t sign, according to The New Stack.

The text calls distillation a “widely used technique” and asks policymakers not to conflate legitimate model development with illegal extraction. Per Axios, OpenAI shares Anthropic’s position in warning Washington about powerful Chinese open weights.

Separately, nearly 200 startups, among them Y Combinator and Proton, urged Trump through the Little Tech Association to use “a scalpel, not a sledgehammer.” Anthropic spent more on federal lobbying in the first half of this year than it did in all of 2025.