"The US Supreme Court has allowed a lawsuit against the Vatican Bank to go forward, despite arguments that the suit involved foreign-policy issues that are not within the jurisdiction of American federal courts. ... The suit, first filed in a California court in 1999, alleges that the Vatican Bank and the Franciscan order profited from assets seized by Nazi leaders from Jewish prisoners at concentration camps during World War II." (Catholic World News; Associated Press). More on suits against the Vatican in U.S. courts here, here and here.
Foreign sovereign immunity watch