[The United States' three major closed-source frontier AI labs—OpenAI, Anthropic, and Google—have not yet signed Jensen Huang's joint open letter] According to a report by Golden Finance, Jensen Huang posted his first tweet on the X platform (formerly Twitter), attaching a joint open letter titled 'Open Weights and America's Leadership in AI.' However, as of now, the United States' three major closed-source frontier AI labs—OpenAI, Anthropic, and Google—have not signed the joint open letter. More than 20 companies that have jointly signed include NVIDIA, Meta, Microsoft, Palantir, CrowdStrike, IBM, ServiceNow, Hugging Face, Mistral AI, a16z, Y Combinator, and Perplexity, among others. It is reported that the open letter advocates against restricting 'AI distillation' technology and states that the measure of America's leadership in AI should not be the strength of a single frontier model but rather the ability to build a robust and open ecosystem that permeates all industries. Open-weight models are the cornerstone of this ecosystem.