This top secret project enables the NSA and FBI to tap directly into the servers of nine leading US Internet firms, providing access to e-mails, documents, audio and video chats, pictures, and much more. The program started on September 11, 2007, on that date PRISM kicked off a collaboration with Microsoft. Over the next couple of years, the program expanded with Yahoo, Google, Facebook, PalTalk, YouTube, Skype, AOL and Apple.
According to the newspapers’ reporting, PRISM began with Microsoft being the first company to cooperate with the government’s secret digital dragnet—on September 11, 2007. Allegedly the most recent collaborator was Apple, beginning in October 2012. The reports state that companies are given immunity from federal prosecution in exchange for opening access to their servers to the FBI’s Data Intercept Technology Unit.Full details about PRISM can be read at ARS Technica.
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A senior administration official commented on the program, saying that it did not try to target US citizens: "The Guardian and Washington Post articles refer to collection of communications pursuant to Section 702 of the Foreign Intelligence Surveillance Act. This law does not allow the targeting of any U.S. citizen or of any person located within the United States,” the official said. “The program is subject to oversight by the Foreign Intelligence Surveillance Court, the Executive Branch, and Congress. It involves extensive procedures, specifically approved by the court, to ensure that only non-U.S. persons outside the U.S. are targeted, and that minimize the acquisition, retention and dissemination of incidentally acquired information about U.S. person."