Lawyers in the U.S. and U.K. filed a joint class-action lawsuit on Tuesday against Facebook, Cambridge Analytica, and two other companies, accusing them of misusing the personal data of 71.6 million Facebook users, The Guardian reports. The suit claims that Cambridge Analytica, SCL Group Limited and Global Science Research Limited improperly collected data from the platform, and Facebook "failed to act responsibly to protect" users' data. Former White House adviser Steve Bannon is named in the lawsuit, as he was the vice president of Cambridge Analytica from 2014 to 2016. Aleksandr Kogan, the founding director of GSR, is also named in the lawsuit. “Facebook has made billions of dollars selling advertisements targeted to its customers, and in this instance made millions selling advertisements to political campaigns that developed those very ads on the back of their customers’ own … personal information,” Richard Fields, co-lead counsel of the lawsuit, told The Guardian. “That’s unacceptable, and they must be held accountable.” Facebook CEO Mark Zuckerberg is expected to testify in front of Congress Tuesday afternoon.