Chinese large model enters openai's enterprise payment system for the first time

On September 30, 2026, Baseten, an American AI infrastructure company, announced a partnership with OpenAI, becoming one of the first open-source model inference service providers in OpenAI's B2B market. This marks the first time Chinese open-source models have entered OpenAI's enterprise procurement system. Enterprise users can now access models like Kimi K3 and GLM 5.3 through Codex. Kimi K3, developed by Moonshot, is the first open-source model with a parameter scale of 2.8 trillion. It natively supports visual capabilities and has a 1 million token context window, making it ideal for long-term programming and multi-document analysis. OpenAI enterprise users can now call these open-source models via Codex or Responses API, gaining more AI capabilities at the same cost. Baseten ensures all models run on U.S. servers and implements zero data retention for all prompts.