Renaissance

Renaissance Technologies hires mathematicians, physicists, and computational linguists, and almost no one from Wall Street. Jim Simons, who had chaired the math department at Stony Brook, founded it in 1982 a short drive away in the Long Island village of East Setauket, and ran it like a graduate science department that happens to trade. The methodology is a genuine black box: even staff who write the code reportedly cannot follow the whole system.

Its flagship Medallion fund, launched in 1988, has been closed to outside money since 1993, open only to employees and their families, while separate institutional funds take external capital on related but distinct approaches. The secrecy runs deep enough that the firm publicly warns which two web addresses are actually its own. Simons died in 2024; the system, by design, kept running without him.