Exclusive – Yahoo secretly scanned customer emails for U.S. intelligence according to sources

Exclusive – Yahoo secretly scanned customer emails for U.S. intelligence according to sources :

Reuters was unable to determine what data Yahoo may have handed over, if any, and if intelligence officials had approached other email providers besides Yahoo with this kind of request.
According to two of the former employees, Yahoo Chief Executive Marissa Mayer’s decision to obey the directive roiled some senior executives and led to the June 2015 departure of Chief Information Security Officer Alex Stamos, who now holds the top security job at Facebook Inc .

Mayer bought Tumblr too.. I would suppose messages on Tumblr would eventually be known to be in the same boat?