Testimony for Congress: Chinese open models now lead American ones

On 21 September, Nathan Lambert, author of the Interconnects newsletter, published an expanded version of testimony prepared for Congress on the state of open ai models.

The numbers

• On the Artificial Analysis Intelligence Index, the top American open model sits behind 15 Chinese-made models.
• Chinese open-weight models are roughly 2 to 5 months behind the closed American frontier.
• American open-weight models are about 6 to 9 months behind OpenAI and Anthropic.
• More US firms are releasing open models, including Arcee AI, Poolside and IBM, but they aren't closing the gap.

On the live leaderboard, the top open-weights model is currently MiMo-V2.6-Pro, at 46, against closed leaders around 53.

Why it matters

This is a snapshot, with numbers, of who leads in open models, and it feeds straight into US policy. It cuts against the assumption that American labs lead everywhere. For anyone who wants ai they can look inside, the open frontier is close behind the closed one, and closing.