DigitalFacebook Signs Letter Seeking More Transparency From Federal Government On National Security Data RequestsFacebook was among the more than 60 companies, investors, civil-liberties groups, and trade groups to sign a letter to top federal government officials requesting the ability to disclose more information about data requests related to national security, Time reported, as fallout from the National Security Agency’s Prism initiative continues.By David Cohen|July 19, 2013ShareBy David Cohen|July 19, 2013SharePages: 1 2 Adweek Adweek