A former Facebook insider speaks out in an on-camera interview with FRONTLINE. Subscribe on YouTube: bit.ly/1BycsJW Long before news broke that Cambridge Analytica had harvested information from Facebook users to help Donald Trump’s 2016 campaign, Sandy Parakilas says he warned Facebook executives of dangers that users’ data could be misused by third-party apps. Drawn from a special FRONTLINE investigation, coming to PBS Fall 2018. Twitter: twitter.com/frontlinepbs Facebook: www.facebook.com/frontline Instagram: www.instagram.com/frontlinepbs FRONTLINE is streaming more than 200 documentaries online, for free, here: to.pbs.org/hxRvQP FRONTLINE is made possible by PBS and CPB. Major support is provided by The John D. and Catherine T. MacArthur Foundation. Additional funding is provided by the Abrams Foundation, the Park Foundation, the John and Helen Glessner Family Trust and the FRONTLINE Journalism Fund with major support from Jon and Jo Ann Hagler on behalf of the Jon L. Hagler Foundation. Support for digital video is provided by the Lisa and Douglas Goldman Fund.