Hartford Fire Insurance Co. v. California, 509 U.S. 764 (1993), was a controversial United States Supreme Court case which held that foreign companies acting in foreign countries could nevertheless be held liable for violations of the Sherman Antitrust Act if they conspired to restrain trade within the United States, and succeeded in doing so.

When U.S. states (including the named plaintiff, California) filed a lawsuit alleging antitrust violations, the defendant companies raised a number of defenses, asserting that the United States lacked jurisdiction over their acts, that various statutes exempted them from liability, and that principles of comity dictated that they should not be brought before a U.S. court.

The Court also found that, in enacting the FTAIA, the U.S. Congress did not intend to write principles of comity into the Sherman Act - but even if they had, this would not affect the outcome.

Nevertheless, the Court looked to the Restatement (Third) Foreign Relations Law, § 415, Comment j for the principle that: Furthermore, the Court cited Restatement (Third) Foreign Relations Law, § 403, Comment e for the proposition that no conflict exists "where a person subject to regulation by two states can comply with both."

Nevertheless, Scalia contended that the actions of the U.S. courts showed a lack of judicial respect for the comprehensive regulatory scheme enacted by the UK.