Mistral AI launched a public preview of its Mistral Large 4 model on October 6, 2026, a 1.05-trillion-parameter multimodal mixture-of-experts system with roughly 52 billion active parameters per token. The preview API is live on Mistral Studio, and the company plans to release open weights by the end of October—most reports point to October 27—following additional safety testing with cybersecurity partners and government authorities. This ends a roughly five-month gap since the prior major release and positions the model as a leading open-weight option outside China, with strong reported results in coding, cybersecurity, finance, and visual grounding. The timing reflects ongoing reinforcement learning and infrastructure scaling funded by recent equity rounds, while competitive pressure from U.S. and Chinese labs continues to shape release cadence. Traders should watch for any last-minute delays in the weights drop or benchmark revisions that could influence market-implied odds around near-term resolution.