Meta releases Muse Spark Open — open-weight 816B model
Meta launched Muse Spark Open on October 15, an open-weight model with 816B total parameters (42B active) and a 1M-token context, built for coding and long-horizon agentic work. Meta claims it rivals leading Chinese open models like Qwen and Kimi K3. Notably, it is optimized to run on Apple's M5 Ultra chips — an unusual Meta-Apple collaboration.