Harmonic

Harmonic is building mathematical superintelligence. Their flagship product, Aristotle, is an AI reasoning engine that achieved Gold Medal–level performance at the 2025 International Mathematical Olympiad and set state-of-the-art results on the VERINA Code Verification Benchmark. Founded in 2024 by Vlad Tenev (co-founder of Robinhood) and Tudor Achim. Harmonic raised a $120M Series C in November 2025 at a $1.45B valuation, led by Ribbit Capital with participation from Sequoia Capital, Index Ventures, Kleiner Perkins, Emerson Collective and Nvidia's NVentures, bringing total funding to roughly $295M.