Microsoft is challenging a US search warrant for customer emails stored on a data center outside the country, and tech companies are lining up in support.
Apple and Cisco are the latest to file a friend-of-the-court brief backing the software giant's position. The joint filing, made Friday, is in addition to ones earlier in the week by Verizon and AT&T showing their support.
The Electronic Frontier Foundation also filed a friend-of-the-court brief Friday, saying US warrants don't apply to emails stored on an overseas server.
"The Fourth Amendment protects from unreasonable search and seizure. You can't ignore the 'seizure' part just because the property is digital and not physical," said EFF Staff Attorney Hanni Fakhoury in a statement Friday. "Ignoring this basic point has dangerous implications -- it could open the door to unfounded law enforcement access to and collection of data stored around the world."
Court papers made public Monday detail Microsoft's objections to complying with a December warrant for a customer's email data stored in Dublin, Ireland, that the US government is seeking in connection with a criminal investigation.
"The government takes the extraordinary position," the filing reads, "that by merely serving such a warrant on any US-based email provider, it has the right to obtain the private emails of any subscriber, no matter where in the world the data may be located, and without the knowledge or consent of the subscriber or the relevant foreign government where the data is stored."
The government, on the other hand, said in its own filing in April that Microsoft's position would lead to "absurd" and "arbitrary" results that would have "a devastating impact on the government's ability to conduct criminal investigations."
Edward Moyer contributed to this report.