Several Internet companies have struck an agreement with the U.S. government to release limited information about the number of surveillance requests they received.
Facebook became the first to release aggregate numbers of requests, saying in a blog post that it received between 9,000 and 10,000 requests for user data in the second half of 2012, covering 18,000 to 19,000 of its users' accounts.
Microsoft said it received between 6,000 and 7,000 requests during the same period, affecting between 31,000 and 32,000 consumer accounts.
The number include requests from state and local governments, as well as those from the National Security Agency.
The companies, which also include Apple, Google and Yahoo, have denied claims the NSA could directly access their servers.
They are are pressuring the Obama administration to further loosen its legal gag preventing them from releasing information about the government surveillance orders.
The companies are seeking to distance themselves from the Internet dragnet code-named "PRISM'' revealed in leaks last week.
U.S. authorities have said the program helped prevent terror attacks.