The National Security Agency and the FBI are tapping directly into the central servers of nine leading U.S. Internet companies, extracting audio and video chats, photographs, e-mails, documents, and connection logs that enable analysts to track foreign targets, according to a top-secret document obtained by The Washington Post...Several companies...said they had no knowledge of the program, did not allow direct government access to their servers and asserted that they responded only to targeted requests for information...Government officials and the document itself made clear that the NSA regarded the identities of its private partners as PRISM’s most sensitive secret, fearing that the companies would withdraw from the program if exposed..[T]he FBI and NSA would be hard pressed to build in back doors without active help from each company...Firsthand experience with these systems, and horror at their capabilities, is what drove a career intelligence officer to provide PowerPoint slides about PRISM and supporting materials to The Washington Post in order to expose what he believes to be a gross intrusion on privacy. [Refers to Apple, AOL, Dropbox, Facebook, Google, Microsoft, PalTalk, Skype (part of Microsoft), Twitter, Yahoo, YouTube (part of Google)]