After reaching a deal with the FBI to publish approximate data on requests for user accounts, Microsoft joined Google in demanding permission from the government to specify which requests were part of FISA. Courtesy /

Microsoft Corporation (NASDAQ:MSFT) has joined Google Inc. (NASDAQ:GOOG) in demanding greater transparency in government requests for user data. On June 19, in a motion filed with the Foreign Intelligence Surveillance Court, Microsoft asked for permission to disclose information on secret FISA requests separate from other government requests.

In the wake of Edward Snowden’s leak of secret surveillance programs such as PRISM, tech companies including Google sought to assuage customer's concerns the government was collecting and monitoring all of their data. Microsoft, along with Apple Inc.(NASDAQ:AAPL), Yahoo Inc. (NASDAQ:YHOO) and Facebook Inc. (NASDAQ:FB), reached a deal with the FBI to reveal information about FISA requests to users with the condition that they only give estimates that lump national security requests together with more general requests.

In the second half of 2012, Microsoft said it received between 6,000 and 7,000 requests, seeking information from as many as 32,000 different Microsoft accounts. These thousands of requests to the Redmond, Wash., company included local authorities searching for missing persons, criminal investigations and national security requests.

Google, of Mountain View, Calif., chose not to disclose this information unless it was able to distinguish between the different types of requests.

“We have always believed that it’s important to differentiate between different types of government requests,” Google told AllThingsD. “We already publish criminal requests separately from National Security Letters. Lumping the two categories together would be a step back for our users.”

Google sent a public letter to the U.S. Attorney General asking for permission to differentiate the types of requests, arguing that doing so wouldn't hurt national security.

When Microsoft published this data initially, John Frank, its vice president and deputy general counsel, said in a blog post that the company knew the numbers weren’t enough to ease customers’ privacy concerns and that it would take further steps in the future. Now, Microsoft is taking legal action in solidarity with Google.

"Disclosure of the aggregate data would not plausibly jeopardize the secrecy of any particular FISA or FAA [FISA Amendments Act] directive that Microsoft may have received," the company said in the court filing. Microsoft went a step further, saying that not being allowed to publish this data is actually a violation of the company’s First Amendment rights.

"The First Amendment does not permit the government to bar Microsoft from speaking about an issue of great importance to its customers, shareholders, and the public while, simultaneously, senior government officials are speaking publicly about the very same subject," Microsoft said.

The government maintains that secrecy about these requests is imperative to national security. Officials from the National Security Agency and the FBI appeared in Washington last week to defend programs such as PRISM, arguing that they've helped thwart nearly 50 terrorist attacks in recent years.

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