The debate in Silicon Valley over whether AI should pursue open-source or closed-source models continues to intensify. As of the morning of July 28, the joint open letter "Open Weights and America's AI Leadership," initiated by NVIDIA, Microsoft, Meta, and others, has grown from an initial 25 signatories to 77 companies and organizations.
Even more striking, OpenAI has joined the coalition —the company that previously championed the closed-source route. It "defected" to the open-source camp, while Anthropic, Amazon, Apple, and other major players have yet to appear on the list.
The intensifying debate is directly driven by the rapid catch-up of Chinese open-source models. According to The New York Times, two individuals familiar with internal discussions at OpenAI and Anthropic revealed that the progress of Chinese AI is making executives at both U.S. companies uneasy, with growing concerns over their long-held leadership advantage shrinking. Meanwhile, U.S. Treasury Secretary Scott Bessent has threatened that Washington is investigating whether Chinese models are engaged in violations of intellectual property rights.
OpenAI's "defection" is a highly symbolic signal. When the open-source coalition now includes Microsoft, NVIDIA, Meta, and even OpenAI, the closed-source camp is facing increasing isolation. Anthropic's persistence, on the other hand, feels more like a "last stand" for its business model.