"“It isn’t a clear-cut answer in terms of who has access to or can compel production of the Panama Papers,” said Albert Gidari, director of privacy at the Stanford Center for Internet and Society.
Foreign governments have, in the past, compelled American companies to disclose data, but Gidari said the legal justification for that is still far from settled. “That is the subject of a lot of discussion today,” he said. “There certainly are cases where that has happened, just as the U.S. has forced subsidiaries of foreign companies operating in the U.S. to disclose data. But many companies have blocking statutes and require data requests to go through formal procedures.”
Gidari said the location of the data itself shouldn’t necessarily matter if Amazon is subject to the jurisdiction of the country making the data request, but even that is up for debate. In fact, Microsoft is currently embroiled a legal battle that hinges on this very issue, fighting a U.S. search warrant for emails stored in Ireland. The case is now in the 2nd U.S. Circuit Court of Appeals."