Microsoft has forced US Federal Bureau of Investigation (FBI) to back down after successfully challenging a secret request from the agency to hand over data from one of its Office 365 customers.
Court documents reveal a National Security Letter (NSL) sent by the FBI to Microsoft last year requesting "several categories of information" about a single, unnamed enterprise customer. The letter came with a default 'gag order,' which implies that the company can't disclose the request even to its customer.
Commenting on his blog, Microsoft chief counsel Brad Smith said, "Last December I announced that Microsoft was committed to notifying business and government customers if we receive legal orders related to their data."
"Where a gag order attempts to prohibit us from doing this, we will challenge it in court."
Microsoft challenged the order on various grounds, citing it as 'constitutional' and 'violating free speech rights.'
The power of NSL was enhanced by the Patriot Act after 9/11.
While Microsoft win was hailed, few privacy advocates remain skeptical as the court documents reveal that the agency was able to get data through 'lawful means from a third party' and voluntarily withdrew NSL request.
Tech companies in the US are increasingly becoming proactive in warding off data requests from government in wake of last year's NSA spying scandal disclosures by Edward Snowden. Last year, Google became the first major tech company to challenge NSLs in court.