Mistral AI launched Mistral Large 4 ("Le Chonk"), a 1.05-trillion-parameter multimodal mixture-of-experts model with 49-52 billion active parameters and a 1-million-token context window, in public API preview on October 6, 2026. The release ends a roughly five-to-ten-month gap since Large 3 and positions the model as a leading open-weight option outside China, with strong reported results in coding, cybersecurity, finance, and visual grounding. Weights are scheduled for release around October 27 following safety testing with partners and governments. Ongoing reinforcement learning shows continued headroom, and Mistral has stated that Large 4 serves as the foundation for rapid subsequent improvements and specialized variants on expanded European compute. Traders should watch the weights drop and any follow-on model announcements for signals on the timeline to a 4.1+ release.