Antitrust Division ATR

The Sherman Antitrust Act of 1890 outlawed monopolization and agreements in restraint of trade, and the Justice Department used it to break up Standard Oil and American Tobacco in 1911. A separate Antitrust Division took shape in 1919, and since 1933 it has been led by an Assistant Attorney General confirmed by the Senate. It shares civil antitrust enforcement with the Federal Trade Commission but alone can bring criminal antitrust cases.

The division prosecutes price-fixing, bid-rigging, and market allocation cartels as crimes that can bring prison sentences and large fines. It reviews proposed mergers under the Hart-Scott-Rodino Act of 1976, which requires large deals to be reported in advance, and can sue to block those that would substantially lessen competition. It also sues dominant firms for monopolization, as in the landmark case against Microsoft that ended in a 2001 settlement.

Antitrust enforcement against the largest technology companies became a bipartisan priority in the 2020s. A federal judge ruled in 2024 that Google illegally monopolized online search, and in 2025 another ruled that it monopolized parts of the advertising technology market, while the division also sued Apple, Live Nation, and Visa. In September 2025 the search judge declined to order Google to sell its Chrome browser and imposed limits on exclusive contracts and data-sharing requirements instead, and on September 2, 2026 the ad tech judge rejected a forced sale of Google's ad exchange and ordered behavioral changes. Debates over how aggressive enforcement should be, and whether settlements are shaped by political pressure, recur across administrations.