[DEVELOPING] Meta releases Muse Spark Open, an 816B-parameter open-weight model, while keeping top models closed
Meta released open weights for Muse Spark Open, a mixture-of-experts model with 816B total and 42B active parameters, aimed at coding and agent work and able to run on two M5 Ultra Mac Studios. SiliconANGLE reports a license that requires a separate agreement for hosted services above $20M in 12-month gross revenue; the Muse Wonder models stay closed. By Meta's own figures, the model trails Chinese open models on Terminal-Bench 2.1 but leads on MCP-Atlas. This adds a large US open-weight option to the open-model price competition; watch for independent evaluations and the full safety report Meta says is pending.