Zuckerberg’s appearance before a joint Senate committee hearing Tuesday went on for nearly five hours and saw him take responsibility for mistakes in protecting users privacy.
Zuckerberg told senators that the company had been contacted by special counsel Robert Mueller’s office and that they were working with Mueller in the investigation into Russian interference in the 2016 presidential election.
Zuckerberg also acknowledged that information from Facebook users sold to political research firm Cambridge Analytica was also shared with other companies.
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Zuckerberg will be testifying before the House Energy and Commerce Committee beginning at 10 a.m. ET Wednesday. According to the committee website, the hearing will “shed light on Facebook’s use and protection of user data, and will help all Americans better understand what happens to their personal information online.”
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Zuckerberg was invited to testify before Congress after Facebook officials initially admitted last week that 50 million of its users had information “improperly shared” when a British psychologist “scraped” data from people who took an online quiz and provided personal information to a firm that used the information to profile potential voters.
A few days later, that number was amended as the company's chief technical officer, Mike Schroepfer, said that instead of 50 million people having their information improperly shared with the political research firm Cambridge Analytica, "In total, we believe the Facebook information of up to 87 million people — mostly in the U.S. — may have been improperly shared" with the company.
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In addition to addressing concerns over the sharing of information, the company has faced questions about political ads and posts on the site prior to the 2016 presidential election.
Live updates of the hearing begin here at 9:45 a.m. ET.