#1 Edward Snowden

Leak: NSA collection of U.S. citizens' phone and Internet records (2013)

Edward Joseph Snowden is a US former technical contractor for the National Security Agency (NSA) and Central Intelligence Agency (CIA) employee who leaked details of top-secret US and British government mass surveillance programs to the press.

Working primarily with Glenn Greenwald of London's The Guardian, which published a series of exposés based on Snowden's disclosures in June 2013, Snowden revealed information about a variety of classified intelligence programs, including the interception of US and European telephone metadata and the PRISM and Tempora Internet surveillance programs. Snowden said the leaks were an effort "to inform the public as to that which is done in their name and that which is done against them".

On June 14, 2013, US 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 to an unauthorized person; the latter two allegations are under the Espionage Act.

Snowden's leaks are said to rank among the most significant breaches in the history of the NSA. He is currently in the process of seeking asylum from U.S. prosecution.

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