How do U.S. antitrust laws affect international business?

All U.S. firms are subject to the antitrust laws of the United States, no matter where their operations or their anticompetitive behavior occurs. Firms from other countries operating in the United States or engaging in trade that has a substantial impact in the United States are also subject to U.S. antitrust laws. U.S. firms are also subject to other countries' antitrust laws if they want to do business in those countries.
In 1982, the Export Trading Company Act allowed large U.S. firms that would otherwise be prohibited from merging to form export trading companies for the purpose of participating in international trade.

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