PRISM, a "Special Source Operation" in the tradition of NSA's intelligence alliances with as many as 100 trusted U.S. companies since the 1970s, was first revealed
The Terrorist Surveillance Program was implemented in the wake of the September 11 attacks under the George W. Bush Administration but was widely criticized and challenged as illegal, because it was conducted without approval of the Foreign Intelligence Surveillance Court.
PRISM was first publicly revealed after classified documents about the program were leaked to The Washington Post and The Guardian by Edward Snowden. The leaked documents included 41 PowerPoint slides, four of which were published in news articles. The documents identified several technology companies as participants in the PRISM program, including Microsoft (2007), Yahoo! (2008), Google (2009), Facebook (2009), Paltalk (2009), YouTube (2010), AOL (2011), Skype (2011), and Apple (2012).
Snowden is a former technical contractor and CIA employee who worked for Booz Allen Hamilton, a contractor for the National Security Agency (NSA). On June 14, 2013, U.S. federal prosecutors filed a sealed complaint, made public on June 21, charging Snowden with theft of government property, unauthorized communication of national defense information and willful communication of classified intelligence with an unauthorized person; the latter two allegations are under the Espionage Act.
Snowden explained his actions saying: "I don't want to live in a society that does these sort of things [surveillance on its citizens]… I do not want to live in a world where everything I do and say is recorded."