Hartford Fire Insurance Co. v. California 509 U.S. 764 (1993) Various reinsurance companies in the UK conspired to coerce US insurers into abandoning certain policy practices that were beneficial to consumers, but costly to the reinsurers. All of this conspiracy occurred in the UK, none of it occurred in the US. The conduct the UK companies were accused of was perfectly legal within the UK. Some States (including California) sued, claiming that the UK companies had violated the Sherman Anti-Trust Act. The UK companies argued that the US lacked jurisdiction over their acts, and that principles of comity dictated that they should not be sued in the US. The Trial Court found that there was no jurisdiction and dismissed the case. California appealed. The Appellate Court reversed and found they had jurisdiction. The UK companies appealed. The US Supreme Court affirmed and found the US had jurisdiction. The US Supreme Court found that foreign companies acting in foreign countries could nevertheless be held liable for violations of the Sherman Anti-Trust Act if they conspired to restrain trade within the US, and succeeded in doing so. The Court looked to the Restatement of Foreign Relations Law §415(j), and noted that: "The fact that conduct is lawful in the state in which it took place will not, of itself, bar application of the United States antitrust laws, even where the foreign state has a strong policy to permit or encourage such conduct." Basically this case said that US laws can apply, so long as those law do not conflict with the laws of the country in question (in this case the UK). Under the reasoning in this case, if it would be possible to comply with both UK and US anti-trust laws, you may apply US laws in a US court, even if the alleged acts took place in the foreign country. On the other hand, if US law was contrary to the laws in the foreign country, and it is impossible to comply with both, then comity dictates that US law cannot apply.