Antitrust

Antitrust is the body of law, and the regulators who enforce it, that polices competition and stops companies from building or abusing a dominant market position. In the US, the FTC and the Justice Department enforce these rules alongside state attorneys general, and the European Union and other regions run their own competition regulators.

Antitrust action can take several forms: blocking a merger or acquisition that would reduce competition, fining a company for unfair practices, forcing changes to how it sells or prices its products, or in the most serious cases, requiring a company to split off part of its business.

For investors, antitrust is a risk that grows with success. The more dominant a company becomes, the more attention it draws from regulators. Cases often take years to resolve, which makes the outcome hard to price, but a ruling can change how a company is allowed to run its most profitable businesses. Checking which cases are open, and which parts of the business they target, helps size how much of the company's profit is exposed.