Exxon Mobil

John D. Rockefeller founded Standard Oil of Ohio in 1870 and built the most dominant corporate monopoly in American history. Through aggressive pricing, secret railroad rebates, and systematic acquisition of competitors, Standard Oil controlled 90% of U.S. oil refining by 1879. Rockefeller became the wealthiest person in American history — his fortune, adjusted for inflation, was larger than those of Bill Gates and Jeff Bezos combined.

The U.S. Supreme Court ruled in 1911 that Standard Oil violated the Sherman Antitrust Act and ordered it broken into 34 separate companies. Among the successors were Standard Oil of New Jersey — which became Exxon — and Standard Oil of New York — which became Mobil. The breakup was intended to reduce Rockefeller's power. Instead, the separate companies' combined value quickly exceeded Standard Oil's as a whole, making Rockefeller even wealthier.

On March 24, 1989, the Exxon Valdez oil tanker ran aground in Alaska's Prince William Sound, spilling 11 million gallons of crude oil. Exxon's response was widely criticised as slow and inadequate. The company was eventually ordered to pay $5 billion in punitive damages — later reduced to $507.5 million by the Supreme Court after 19 years of litigation. The disaster remains the defining corporate environmental crisis in American history.

Exxon acquired Mobil in 1999 for $81 billion — at the time, the largest corporate merger in history. The two companies, separated by antitrust regulators 88 years earlier, were reunited as ExxonMobil. The merger created the world's largest publicly traded company by market capitalisation.

ExxonMobil completed its $60 billion acquisition of Pioneer Natural Resources in May 2024 — the largest oil and gas deal in over two decades. The acquisition doubled ExxonMobil's presence in the Permian Basin, the most productive oil field in the United States, adding 850,000 barrels per day of production capacity. ExxonMobil simultaneously expanded its investments in carbon capture and low-emissions energy — while producing more oil than at any point in its post-Rockefeller history. The company that activists had attempted to disrupt with a board campaign in 2021 had responded by growing larger.