Model · Language model
Step 3.5 Flash
StepFun's 196-billion-parameter sparse MoE flagship reasoning release with 11B active parameters, published as Apache-declared open weights with a managed API.
- Developer
- StepFun
- Distribution
- Downloadable weights · Developer API
- Artifact licensing
- Open-licensed artifacts
- License scope
- Reviewed release artifacts and mandatory terms; not an assessment of training code or training data openness.
- Licenses
- Apache License 2.0
- Boundary
- This record represents the February 2026 Step-3.5-Flash release at Hugging Face commit ab446a3de5e171ea341227e24bb1f090e1b771f7 (last modified 2026-03-17), together with the step-3.5-flash API model. The 2603 agent-optimized variant, the 3.7 successor, and community quantizations remain separate boundaries.
Risk statements
Not yet examined.
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