Facebook chief executive Mark Zuckerberg has navigated through the first of two US congressional hearings without making any further promises to support new legislation or change how the social network does business.
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During nearly five hours of questioning by 44 US senators, Mr Zuckerberg repeated apologies he previously made for a range of problems that have beset Facebook, from a lack of data protection to Russian agents using Facebook to influence US elections.
But the 33-year-old internet mogul managed to deflect any specific promises to support any congressional regulation of the world's largest social media network and other US internet companies.
Investors were impressed with his performance with Facebook shares posting their biggest daily gain in nearly two years, closing up 4.5 percent.
The shares fell steeply last month after it came to light that millions of users' personal information was harvested from Facebook by Cambridge Analytica, a political consultancy that has counted US President Donald Trump's election campaign among its clients.
The latest estimate of affected users is up to 87 million.
That disclosure pitched Facebook into a crisis of confidence among users, advertisers, employees and investors who were already struggling with Facebook's reaction to fake news and its role in the 2016 election.
The crowded Senate hearing was not without theatrics, although most was from the audience, like an activist dressed in costume as a Russian internet "troll" and an extra cushion on Mr Zuckerberg's chair that was dubbed his "booster seat."
Wearing a dark suit and tie instead of his typical T-shirt and jeans, Mr Zuckerberg remained largely unruffled and serious as senators questioned him. But some senators did provoke a reaction.
Mr Zuckerberg was asked whether Facebook was a monopoly. "It certainly doesn't feel that way to me," he said, breaking into a smile as the audience laughed.
But the senators who asked sharp questions were often at a disadvantage because each had only five minutes to pin down the billionaire.
Facebook disclosed in September that Russians under fake names used the social network to try to influence US voters in the months before and after the 2016 election, writing about inflammatory subjects, setting up events and buying ads.
When asked if there was overlap between Cambridge Analytica's harvested user data and the political propaganda pushed by the Kremlin-linked Internet Research Agency during the 2016 presidential election, Mr Zuckerberg said a connection is entirely possible.
The US Federal Trade Commission is investigating whether Facebook violated an agreement it signed with the agency in 2011 by its actions in the Cambridge Analytica scandal.
Last week, Mr Zuckerberg threw his support behind proposed legislation, known as the Honest Ads Act that would require social media sites to disclose the identities of buyers of online political campaign ads, but on Tuesday, would not agree to speak out further on behalf of the Honest Ads Act.
A second session before a House of Representatives committee is scheduled for Wednesday.