tl;dr: Nvidia, Microsoft, Meta, Palantir and 20+ other tech companies signed a letter urging policymakers not to impose "premature restrictions" on open-weight AI models, arguing such moves would stifle competition and push innovation overseas. The letter comes amid growing concern over Chinese open-weight models like Moonshot's Kimi K3 outperforming U.S. offerings, with the Trump administration weighing potential sanctions over alleged IP theft. Notably, OpenAI and Anthropic—both preparing for IPOs and primarily developing closed models—did not sign, though Sam Altman voiced support on X.