A group of Holocaust victims may not sue Hungary in American courts to recover property stolen during World War II because their funds were comingled with other funds, the Supreme Court ruled Friday in a long-running case about how much reach US courts should have to settle disputes abroad.

The justices unanimously ruled that the plaintiffs had not established a connection to the United States required by the Foreign Sovereign Immunities Act.

Justice Sonia Sotomayor acknowledged that her ruling will make it "harder" for plaintiffs to satisfy an exception to foreign sovereign immunity for stolen property sold for cash.