JOHN D. ROCKEFELLER

John Davison Rockefeller Sr. (1839–1937) co-founded Standard Oil in 1870 and built it into a vertical and horizontal monopoly controlling roughly 90% of American oil refining capacity by 1880. His operational innovations — secret rebate agreements with railroads, predatory pricing, dummy companies, the trust structure itself — were systematic enough that Ida M. Tarbell's nineteen-part exposé in McClure's Magazine (1902–1904) functions as a foundational text of modern investigative journalism.

In 1911, the Supreme Court found Standard Oil in violation of the Sherman Antitrust Act and ordered its dissolution into 34 successor companies, several of which (Exxon, Mobil, Chevron, Amoco) re-aggregated through twentieth-century mergers. Rockefeller's personal stake in the successors made him the wealthiest American in inflation-adjusted history.

His later philanthropy — the University of Chicago, Rockefeller Foundation, eradication of hookworm in the American South — is acknowledged by the Bureau but does not retroactively modify methodology score.