OpenAI’s September 2026 resolution of the Navier-Stokes existence and smoothness problem—one of the remaining Millennium Prize Problems—using an internal model coordinating roughly 10,000 AI agents over days, followed by its October release of 722 papers advancing hundreds of open mathematical questions, has anchored trader sentiment at 62.5% implied probability. These results, verified in Lean and targeting singularities plus variants of the Riemann hypothesis, demonstrate scaled reasoning capabilities that outpace prior benchmarks. Anthropic contributed concurrent progress on related fluid-dynamics problems via employee collaborations and has advanced Riemann zeta bounds and quantum-circuit design with Claude, yet lacks equivalent verified Millennium-scale claims. Key near-term catalysts include independent scrutiny of OpenAI’s proofs and any parallel pushes on unsolved problems such as Yang-Mills.