Robinhood's CEO says the trading app limited buying of GameStop stock 'to protect the firm and protect our customers'

• Robinhood CEO Vlad Tenev told CNBC that the trading app acted to protect itself and its customers.
• "It pains us to have had to impose these restrictions," Tenev said, adding that Thursday was "challenging."
• He said he wanted to make clear that Robinhood "did not do this at the direction of any market maker."

Robinhood CEO Vlad Tenev said on Thursday that the company's move to restrict trading of GameStop, AMC, and other stocks was in the best interest of the app and its users.

"In order to protect the firm and protect our customers, we had to limit buying in these stocks," Tenev told CNBC.

On Thursday, the stock-trading app blocked purchases of 13 equities including GameStop, AMC, BlackBerry, and Nokia. Users were furious, and one even launched a class-action suit against Robinhood. Later in the day, the company announced it would reopen limited purchases of the affected stocks.

Tenev said that Thursday was "a challenging day" and that the firm had to make "a difficult decision" as "part of normal operations."

"It pains us to have had to impose these restrictions," Tenev said, adding that Robinhood would do what it could to enable trading in these stocks soon.

He said he wanted to address misinformation and stressed that the company "did not do this at the direction of any market maker."

"Robinhood is a brokerage firm," he said. "We have lots of financial requirements."

He added: "We just haven't seen this level of concentrated interest marketwide in a small number of names before ... We do believe that you should be able to buy and sell the stocks that you want to."

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He said Robinhood was seeing so much interest because "finance has been culturally relevant in a way that hasn't been before."

Tenev denied that Robinhood had a liquidity problem after Bloomberg reported that the company was said to have borrowed "at least several hundred million dollars" from banks amid the huge surge in trading on its platform. He said he pulled in credit lines as a proactive measure.