Antitrust: Laws, Enforcement, and Why It Matters

Antitrust refers to laws and regulations designed to preserve competition by preventing the concentration of economic power through monopolies, collusion, or other anticompetitive practices. These rules aim to protect consumers and markets by promoting lower prices, higher-quality goods and services, and ongoing innovation.

Key takeaways

• Antitrust laws limit market power and prohibit collusion, price fixing, monopolization, and other practices that harm competition.
• The Sherman Act, the Federal Trade Commission (FTC) Act, and the Clayton Act form the core of U.S. federal antitrust law.
• The FTC and the U.S. Department of Justice (DOJ) enforce antitrust law, each with distinct roles and remedies.

Core antitrust laws

• Sherman Act (1890): Prohibits contracts, conspiracies, and attempts to monopolize or restrain trade (e.g., price fixing, market division, bid rigging). Provides for civil and criminal penalties.
• Federal Trade Commission Act (1914): Bars unfair methods of competition and deceptive acts; created the FTC to investigate and pursue administrative and civil remedies.
• Clayton Act (1914): Addresses specific practices the Sherman Act doesn’t expressly cover (for example, certain types of mergers and interlocking directorates) and authorizes premerger review of transactions.

Note: The Interstate Commerce Act (1887) was an earlier step toward regulating monopolistic conduct (railroads) but the Sherman, FTC, and Clayton Acts are the main federal antitrust statutes today.

Who enforces antitrust law—and how

• Federal Trade Commission (FTC)
• Enforces antitrust statutes through investigations, administrative complaints, and civil litigation.
• Focuses on consumer-facing sectors with high consumer spending such as technology, healthcare, food, energy, and digital communications.
• Can seek injunctive relief, negotiated settlements, or administrative remedies; may refer criminal matters to the DOJ.
• U.S. Department of Justice (DOJ), Antitrust Division
• Prosecutes criminal antitrust violations and brings civil cases in federal court.
• Has sole antitrust jurisdiction in certain regulated sectors (e.g., telecommunications, banks, railroads, airlines) and can impose criminal sanctions.
• Enforcement may be triggered by premerger filings, complaints from consumers or businesses, congressional inquiries, or investigative reporting.

Courts apply antitrust statutes to the facts of each case, so many prohibited practices are defined through litigation and precedent rather than exhaustive statutory lists.

Common anticompetitive practices

• Collusion and cartels: Agreements among competitors to fix prices, divide markets, or rig bids.
• Monopolization: Dominating a market through exclusionary or predatory conduct rather than superior goods or services.
• Price discrimination: Charging different buyers different prices in ways that harm competition.
• Predatory pricing: Selling below cost to drive rivals out of the market, then raising prices.
• Bid rigging: Manipulating competitive bidding processes.
• Vertical or horizontal restraints: Agreements among firms at the same or different levels of the supply chain that limit competition (e.g., exclusive dealing).

Why antitrust matters

Without antitrust enforcement, dominant firms could reduce consumer choice, increase prices, stifle innovation, and block new entrants. Supporters of antitrust argue these laws protect consumers and the efficient functioning of markets. Critics contend excessive enforcement can interfere with free-market efficiencies.

Major recent example: Google and digital advertising

In 2023 the DOJ, joined by eight states, sued Alphabet/Google alleging it unlawfully monopolized digital advertising technologies. In April 2025 a court found Google liable on two counts, concluding the company had unlawfully monopolized the publisher ad server and ad exchange markets. The government alleged Google used acquisitions and exclusionary conduct to neutralize rivals, limit innovation, and raise ad fees. Potential remedies include divestiture of business lines or other actions to restore competition; Google indicated it would likely appeal.

Remedies and outcomes

Antitrust remedies vary by case and can include:
* Injunctions to stop unlawful conduct
* Divestitures (forcing sale of business units)
* Structural or behavioral remedies to restore competition
* Criminal fines and imprisonment for individuals in cartel cases
* Monetary damages awarded in private lawsuits

Bottom line

Antitrust law is focused on preserving competitive markets by preventing monopolies and collusion. The Sherman Act, FTC Act, and Clayton Act provide the legal framework, while the FTC and DOJ enforce the rules. Enforcement decisions are fact-specific and shaped by litigation, and remedies can range from injunctive relief to divestiture or criminal penalties.

Sources and further reading

• Federal Trade Commission — The Antitrust Laws; The Enforcers
• U.S. Department of Justice — Antitrust Division materials and case filings
• National Archives — Interstate Commerce Act (historical context)