Check out the companies making headlines before the bell: GameStop , AMC Entertainment — GameStop soared more than 77% on speculation that Keith Gill, also known online as Roaring Kitty, has a stake in the company worth $116 million as of Friday’s close. AMC shares jumped about 25% on the renewed meme-stock craze. Waste Management , Stericycle — Shares of medical waste-disposal company Stericycle jumped 16% after Waste Management agreed to buy the company for $7.2 billion. Waste Management fell 1.5%. MarineMax — MarineMax, a recreational boat and yacht services company, popped 19% on a report that OneWater Marine is in talks to buy the company for $40 a share in cash. Bloomberg first reported the deal, citing people with knowledge of the matter. Cava — The Mediterranean fast-casual restaurant chain slipped nearly 2% following a downgrade by JPMorgan to neutral from overweight. The bank cited the stock’s valuation for the call. Cava has soared 115% so far this year. Nvidia , AMD — Chipmakers Nvidia and AMD added 3% and 1.4%, respectively, after the companies each announced new artificial intelligence chips . AMD on Monday announced its new AI chips at the Computex tech conference in Taipei, while Nvidia on Sunday unveiled its next-generation AI chips called “Rubin,” which will succeed its previous “Blackwell” model that was released in March. Bank of America named Nvidia a top pick in a Monday note and kept its price target, which implies about 36% upside for the stock. Boston Beer Company — Shares slid 11% after Bloomberg reported that Japanese brewer and distiller Suntory denied it is in talks to buy the Samuel Adams owner. The Wall Street Journal reported Friday that buyout talks were in the early stages. Best Buy — The electronics retailer added 2.7% on a double upgrade from Citi to buy from sell. Citi said the electronics retailer should see upside to earnings and valuations as consumers replace technology and artificial intelligence lifts demand. Spotify — Shares of the music streaming service rose 4.8% after it announced Monday it will raise prices for Spotify Premium subscriptions in the U.S. starting in July. GSK — The biopharma company tumbled 8.5% after a Delaware court on Friday allowed jury trials in cases brought by cancer patients who claim GSK’s Zantac drug caused their condition . Autodesk — Autodesk surged 6.8% after the software company said it would not restate its financial results following an investigation into its accounting practices. Paramount Global — Shares added more than 6% after Skydance Media revised its buyout offer for Paramount and gave nonvoting shareholders an option to cash out Paramount Class B shares at a roughly 26% premium to Friday’s close. — CNBC’s Alex Harring, Brian Evans and Michelle Fox Theobald contributed reporting.