Open-weight & owned stack · Open lab releases

StepFun previews 600-billion-parameter Step 5

Sep 20, 2026. Covered by 3 outlets.

StepFun previewed a 600-billion-parameter sparse mixture-of-experts model with a one-million-token context window and planned October open-weight release.

Read the original at datastudios.orgOpens the publisher's site in a new tab

Also covering this

Step 5 Preview: China's Cheapest Frontier AI Model Yetintelligentliving.co, Sep 20 StepFun Launches Step 5 Preview: China's 600B AI Model at $1/M Tokenseasternherald.com, Sep 20 StepFun Launches Step 5 Preview: A 600B-Total, 27B-Active MoE Model With 1M Context for Long-Horizon Agentic Work - MarkTechPostmarktechpost.com, Sep 21 StepFun Launches Step 5 Preview: A 600B-Total, 27B-Active MoE Model With 1M Context for Long-Horizon Agentic Work - MarkTechPostmarktechpost.com, Sep 21

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