I map that the publicly‑investable pure‑play supplier surface is razor thin – once you remove the incumbents who keep their data for themselves, the only US‑listed data company of meaningful size selling into the AI boom is Innodata. The social‑media corpus owner’s licensing line is small (~5‑6% of revenue, the rest advertising), and the expert‑evaluation middle (Scale, Surge, Mercor) is entirely private.