Documents from a US federal court reveal that Microsoft has successfully challenged FBI's request seeking information of one of its cloud customers.
According to CNET, the documents revealed that late last year, Microsoft received a National Security Letter which was with regard of one of its customers, seeking basic subscriber information.
The NSL received by the tech giant included a gag order, which prevented the company from notifying its customer about the request, which urged Microsoft to take legal action.
Microsoft's general counsel, Brad Smith said that he had pledged that Microsoft would notify its customers if any legal orders were received relating to their data, and the letter included a non-disclosure provision which violated the company's Constitutional right to free expression.
He added that FBI withdrew its letter after the company filed this challenge.