Microsoft reveals over 75,000 user data requests in 2012 from government agencies

The requests, which included those for the Skype messaging and voice service, potentially impacted 137,424 accounts, Microsoft said on its corporate citizenship Web page.

The disclosure is similar to a "transparency report" which Google started in 2010.

Microsoft said that "customer content" was released in just 2.1 percent of cases, representing 1,558 requests.

But "non content" information, which can include subscriber information such as the e-mail address, name, location and IP address was released in 79.8 percent of requests to the company, excluding Skype.

The company said Skype, which Microsoft acquired in 2011, did not provide any "content" in response to the 4,713 requests but did provide a Skype ID and other identifiers in more than 500 cases.

"In recent months, there has been broadening public interest in how often law enforcement agencies request customer data from technology companies and how our industry responds to these requests," Microsoft general counsel Brad Smith said.

"Google, Twitter and others have made important and helpful contributions to this discussion by publishing some of their data. We've benefited from the opportunity to learn from them and their experience, and we seek to build further on the industry's commitment to transparency by releasing our own data today."

Smith said the data suggests "that less than 0.02 percent of active users were affected" by data requests.

"Microsoft is committed to respecting human rights, free expression, and individual privacy," he said, but added that "like every company, we are obligated to comply with legally binding requests from law enforcement."

Smith said two-thirds of the requests to Microsoft excluding Skype which resulted in any disclosure came from five countries the United States, Britain, Turkey, Germany and France.

For Skype, the top five countries accounted for 81 percent of all requests The US, Britain, Germany, France and Taiwan.

Microsoft said that like Google, it had received so-called National Security Letters from the FBI as part of terrorism investigations, but could not divulge exact numbers.

In 2009 and 2012, Microsoft received between zero and 999 of these requests, and between 1,000 and 1,999 in 2010 and 2011.

A US judge last week ruled that the use of these letters was unconstitutional because it denied due process to citizens. But the judge allowed the measures to remain in place pending an appeal.