Zuckerberg completes Day 1 of testimony

Facebook Inc shares posted their biggest daily gain in nearly two years on Tuesday as Chief Executive Mark Zuckerberg fended off questions from U.S. senators on day one of his testimony on how the world’s largest social network might be regulated more closely.

Zuckerberg repeated apologies made on Monday for a range of problems that have beset Facebook, from data privacy to foreign attempts to influence U.S. elections, but the 33-year-old internet mogul managed to deter any specific talk about new laws and made no new promises.

He denied that Facebook, which has more than 2 billion monthly users across the world, was a monopoly. “It certainly doesn’t feel that way to me,” Zuckerberg said, nearing the end of a nearly 5-hour hearing.

Democratic Senator Catherine Masto from Nevada told him, “Stop apologizing, and let’s make the change. I think it’s time to really change the conduct…The skepticism that I have is over the last what seven years, seven-14 years haven’t seen really much change in ensuring that the privacy is there, and that individual users have control over their data.”

Democratic Senator Jon Tester from Montana told Zuckerberg, “In practice, let’s think about this for a second you’re making about 40 billion bucks a year on the data. And in fact I would say that the the data that was breached through Cambridge Analytica, which impacted and correct me if these numbers are wrong, some 80 million Americans. So could you give me some sort of idea on how you can really, honestly say, it’s it’s my data when, quite frankly, they may have goods on me, I don’t I don’t want them to have any information on me. If I own it, I can stop it.”

Wearing a dark suit and tie instead of his typical T-shirt and jeans, Zuckerberg appeared largely unruffled as senators questioned him.