A May 2015 estimate put the number of fake accounts at 170 million .
A Symantec study in September 2011 found that 15 % of 3.5 million video posts were made through fake likes .
A May 2015 estimate put the number of fake accounts at 170 million , and a Symantec study in September 2011 found that 15 % of 3.5 million video posts were made through fake likes .