Facebook Chief Technology Officer Mike Schroepfer has claimed the tech giant had no idea when it hired social psychology researcher Joseph Chancellor that he’d previously co-founded the company that designed an app which harvested user data on behalf of Cambridge Analytica. Chancellor co-founded Global Science Research alongside data scientist Aleksandr Kogan, who created the This Is Your Digital Life app that harvested user data for Cambridge Analytica. Speaking to British lawmakers on Thursday, in place of Mark Zuckerberg (who refused an invitation to attend), Schroepfer said Facebook executives only found out about Chancellor’s involvement with Global Science Research “fairly recently,” saying they were unaware of his history when they hired him in November 2015. Asked how the information could have escaped the company, Schroepfer said: “I don’t know exactly why we didn’t know, but I’m just telling you the facts I know." Asked when exactly the company found out Chancellor had worked with Kogan in the company that created the app at the center of the Cambridge Analytica scandal, Schroepfer said he believed it was last year.