Meta's 816B Muse Spark Open Narrows the Gap — With Strings
Meta released Muse Spark Open, an 816-billion-parameter mixture-of-experts with 42 billion active, 256 experts per layer, a 1M-token context and native image, video and audio input. It posts 80.4 on OSWorld-Verified and 76.4% on Terminal-Bench 2.1, scores 39 on a leading intelligence index and runs on two top-end Mac Studios at roughly 21 tokens a second in 3-bit form.
The catch is the licence: mandatory "Built with Muse" attribution, a separate deal above $20M a month in revenue, and a usage policy that reaches outputs and derivatives — clouding the synthetic-data use enterprises want most. Several analysts rank it behind GLM-5.3, Kimi K3 and Qwen3.8.