US officials used the authority of the Foreign Intelligence Surveillance Act (FISA) to ask for information from between 9,000 and 10,000 Google user accounts in the first six months of 2013, and between 12,000 to 13,000 accounts in the six months prior to that, according to a blog post.
Release of such data was subject to a six-month delay under terms of an arrangement with the US Department of Justice to let Internet firms be slightly more open about how much information is sought under authority of FISA court orders.
“Publishing these numbers is a step in the right direction, and speaks to the principles for reform that we announced with other companies last December,” Google law enforcement and information security legal director Richard Salgado said in a blog post.
“But we still believe more transparency is needed so everyone can better understand how surveillance laws work and decide whether or not they serve the public interest.”
Google included the FISA request numbers in a routinely released Transparency Report about efforts by governments to legally obtain data from the California-based Internet titan.
Last week, US authorities agreed to give technology firms the ability to publish broad details of how their customer data has been targeted by US spy agencies. The agreement came amid litigation from tech giants Facebook, Google, LinkedIn, Microsoft and Yahoo.
The companies have been seeking the right to release figures on vast surveillance of online and phone communications, in the wake of leaked documents from former National Security Agency contractor Edward Snowden.