Microsoft is challenging the authority of federal prosecutors to force the giant technology company to hand over a customer’s email stored in a data center in Ireland.

The objection is believed to be the first time a corporation has challenged a domestic search warrant seeking digital information overseas. The case has attracted the concern of privacy groups and major United States technology companies, which are already under pressure from foreign governments worried that the personal data of their citizens is not adequately protected in the data centers of American companies.

Verizon filed a brief on Tuesday, echoing Microsoft’s objections, and more corporations are expected to join. The Electronic Frontier Foundation is working on a brief supporting Microsoft. European officials have expressed alarm.

In a court filing made public on Monday, Microsoft said that if the judicial order to surrender the email stored abroad is upheld, it “would violate international law and treaties, and reduce the privacy protection of everyone on the planet.”