Facebook founder and CEO Mark Zuckerberg is widely perceived to have performed well during the first of two US congressional hearings.
During the session, the Facebook boss resisted calls to support new regulations governing the platform, or to change how it conducts its business.
But he admitted that the platform was locked into a constant battle with Russian operators seeking to exploit it.
Zuckerberg faced nearly five hours of questioning by 44 US senators, against a backdrop of the Cambridge Analytica data sharing scandal.
This included its lack of protection against the exploitation of people’s personal data, and its fight against Russian agents trying allegedly to use Facebook to influence US presidential elections.
But the 33-year-old billionaire also managed to fend off repeated attempts to gather his support for additional regulation of the world’s largest social media network and other US tech companies.
Investors were impressed with his performance.
Shares in Facebook posted their biggest daily gain in nearly two years, closing up 4.5 percent.
“I’ll have my team follow up with you so that way we can have this discussion across the different categories where I think this discussion needs to happen,” Zuckerberg told a joint hearing by the US Senate’s Commerce and Judiciary committees, when asked what regulations he thought were necessary.
Zuckerberg’s use of the “I will have my team get back to” was used repeatedly during the hearing to deal with these thorny questions.
One of the admissions from Zuckerberg was that his company was struggling against Russian operators seeking to exploit the social network.
Zuckerberg said Facebook was currently developing new tools to identify fake accounts.
“This is an arms race. They’re going to keep getting better,” he said.
Last week Facebook removed 70 Facebook and 65 Instagram accounts – as well as 138 Facebook Pages – controlled by the Russia-based Internet Research Agency (IRA).
The IRA has been accused by US Special Counsel Robert Mueller being a “Russian troll farm” and trying to influence the 2016 US presidential elections.
Indeed, the Special Counsel has charged 13 Russians with interference in the 2016 election, along with three Russian companies including the IRA.
During the questioning, Zuckerberg admitted that Mueller had interviewed a number of Facebook staff, but not him personally.
“Our work with the special counsel is confidential and I want to make sure that in an open session I’m not revealing something that’s confidential,” Zuckerberg said.
During the hearing, Zuckerberg also denied that Facebook was a monopoly.
“It certainly doesn’t feel that way to me,” he said, breaking into a smile as the audience laughed.
Zuckerberg also made a number of other noteworthy comments during his testimony.
“In retrospect it was clearly a mistake” to believe Cambridge Analytica deleted data, without further examination,” he said.
Zuckerberg also seemed to be suggest at one point that there would always be a free version of Facebook, leaving open the possibility of a paid, ad-free version of the social network.
Zuckerberg ended his Senate appearance just past 2300 GMT, but he will appear in a second session before a House of Representatives committee is scheduled for Wednesday at 1400 GMT.
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