Microsoft CEO Steve Ballmer (L) and Skype CEO Tony Bates (R) speak during a news conference about Microsoft's purchase of Skype on May 10, 2011 in San Francisco, California. - 

New documents, leaked by Edward Snowden and reported in The Guardian newspaper, show Microsoft helped the NSA circumvent its own encryption to intercept Outlook and Skype communications.

Chester Wisniewski, with the cyber security firm Sophos, joins Marketplace Tech host Ben Johnson to discuss.