(Bloomberg) -- GameStop Corp. and AMC Entertainment Holdings Inc. rebounded after Robinhood Markets removed limits on buying the two stocks, which have been at the center of the battle between Reddit-empowered retail traders and short-sellers.Both shares rose Friday, with GameStop’s surge of as much as 78% triggering three volatility halts after whipsawing between gains and losses. It was up about 36% to $72.89 as of 10:34 a.m. in New York. AMC shares were up 4.2% after surging as much as 17%.Robinhood’s move, announced in an update on the trading platform’s support page, comes a day after it increased limits on purchases of the two stocks. Both have skyrocketed since late January as day traders who populate Reddit’s WallStreetBets forum sought to fend off short-sellers.GameStop’s volatile morning came amid a rush of volume over the first hour of trading. With about 40 million shares swapping hands, the rate of buying and selling at the start of the session was double what’s been seen over the past week.GameStop had plunged 84% so far this week through Thursday while AMC tumbled 47% as retail traders flocked to other corners of the stock market, such as small drug developers. Shares of the video game retailer have plummeted 84% since hitting a record intraday peak of $483 last week, reducing its market value by about $28.3 billion to $5.5 billion. The stock is still up 300% this year.Robinhood’s temporary restrictions on the Reddit group’s favorite stocks last week triggered an outcry among retail traders who said the brokerage had sided with hedge funds and institutional money. In order to shore up its capital amid the trading frenzy, the trading app operator has had to borrow or raise billions of dollars.Trading in other Reddit-favored names were mixed Friday morning with Naked Brand Group Ltd. and headphone maker Koss Corp. gaining after initial losses. Cannabis company Sundial Growers Inc., retailer Express Inc., and Ezgo Technologies Ltd. were among other “meme stocks” that erased gains to trade lower. Zomedica Corp. surged as much as 30% before trimming gains.Limits on trading and the quick declines for the likes of GameStop and Express led retail investors to snap up biotechnology companies like Cassava Sciences Inc. The small drug developer has boomed more than 700% this year to become the top stock in the Nasdaq Composite Index. Cassava fell as much as 24% on Friday.Robinhood’s RoleVlad Tenev, the chief executive officer of Robinhood, said in an opinion piece on USA Today this week that the firm built the trading app to serve the millions of people left behind by the U.S. financial system -- not hedge funds.The short-term curbs haven’t damaged the popularity of the no-fee app, founded in 2013. It was downloaded more than 600,000 times last Friday alone, according to research from SimilarWeb and JMP Securities LLC.Robinhood’s Role in the ‘Gamification’ of Investing: QuickTake(Updates with latest share price moves and additional details throughout.)For more articles like this, please visit us at bloomberg.comSubscribe now to stay ahead with the most trusted business news source.©2021 Bloomberg L.P.