OpenAI’s September 2026 announcement that its internal AI agents produced a Lean-formalized proof of finite-time blowup for forced three-dimensional Navier-Stokes equations drove immediate market movement, prompting CMI to label the problem “Active” and state it had “apparently been settled.” Traders are pricing low near-term odds because CMI’s rules require formal publication in a qualifying outlet, broad community acceptance, and a two-year waiting period before any declaration or prize consideration. Ongoing verification debates, including questions around semantic fidelity of the formalization and credit disputes involving researchers at OpenAI and Anthropic, add uncertainty. Key upcoming catalysts include peer-review outcomes and any follow-up CMI updates on evaluation progress.