A US judge has ordered Google to comply with FBI search warrants which ask for customer emails that are stored outside of the US. The ruling is diverging from a recent case in which a federal appeal court ruling concluded that Microsoft did not need to comply with such orders.

U.S. Magistrate Judge Thomas Rueter in Philadelphia ruled on Friday that transferring emails from a foreign server so FBI agents could review them locally as part of a domestic fraud probe did not qualify as a seizure.

The judge said this was because there was "no meaningful interference" with the account holder's "possessory interest" in the data sought.

"Though the retrieval of the electronic data by Google from its multiple data centers abroad has the potential for an invasion of privacy, the actual infringement of privacy occurs at the time of disclosure in the United States," Rueter wrote.

"The magistrate in this case departed from precedent, and we plan to appeal the decision. We will continue to push back on overbroad warrants," said Google.

The ruling came less than seven months after the 2nd U.S. Circuit Court of Appeals in New York said Microsoft could not be forced to turn over emails stored on a server in Dublin, Ireland that U.S. investigators sought in a narcotics case.