Check out the companies making headlines in midday trading: GameStop — The meme stock jumped more than 25% in volatile trading amid speculation that Keith Gill, the man who inspired 2021′s epic short squeeze, could have a huge position in the video game retailer. Gill, who goes by DeepF——Value on Reddit, reappeared Sunday night, posting a screenshot of what could be his portfolio holding five million shares of GameStop common shares worth more than $100 million. He also owned a position of 120,000 GameStop call options. AMC , another meme stock, popped 10%. Both names were also among those affected by a technical issue on the New York Stock Exchange on Monday morning. Waste Management , Stericycle — Waste Management is buying Stericycle for $7.2 billion , the companies announced on Monday. Stericycle shares jumped nearly 15%, while Waste Management slid 4%. Spotify — The music streaming company climbed 4% following its announcement of premium subscription price increases in the U.S. in July. It marks the Swedish company’s second hike in a year. GSK — The pharmaceutical giant fell more than 9% after the Delaware State Court ruled that scientific evidence can be presented in the roughly 75,000 cases alleging the discontinued heartburn drug Zantac may contain a carcinogen. Paramount Global — The media company advanced more than 7% after CNBC’s David Faber reported the firm and Skydance have agreed to terms of a merger, A deal could be announced in the coming days, and it is awaiting sign-off from Paramount’s controlling shareholder Shari Redstone, he reported. Lattice Semiconductor , Coherent — Lattice shares dove 11% after CEO Jim Anderson left to take the helm at Coherent, whose stock price jumped 17%. Esam Elashmawi, Lattice’s marketing and strategy chief, was named interim CEO while the search for a permanent leader takes place. Becton, Dickinson and Company — The medical technology stock advanced 2.6% after announcing it will acquire Edwards Lifesciences ‘ critical care products in a $4.2 billion cash deal . Edwards Lifesciences shares ticked up 0.5%. MarineMax — The boat and yacht services stock surged 24% following a Bloomberg News report that OneWater Marine is in purchase talks with the company. OneWater Marine would pay $40 per share, according to the report, which cited people familiar with the matter. India and Mexico stocks — Equities connected to India and Mexico moved following elections in each country. The iShares MSCI India ETF (INDA) rose 3% and touched a 52-week high as exit polls suggest Prime Minister Narendra Modi and his alliance were poised for a third straight term in power. The iShares MSCI Mexico ETF (EWW) tumbled nearly 9% after Claudia Sheinbaum became the first woman ever to be elected president. Cava — Shares shed about 5% after being downgraded at JPMorgan to neutral from overweight. The bank said the Mediterranean fast-casual restaurant chain’s stock has gotten expensive. Shares have more than doubled in 2024. Nvidia , AMD — AMD is down around 3% after it announced new artificial intelligence chips . Fellow chipmaker Nvidia, which is up 3%, also unveiled a new generation of AI chips on Sunday that will succeed its previous “Blackwell” product, which was released in March. Bank of America kept its price target for Nvidia after naming it a top pick in a note on Monday, implying about 36% upside for the stock. Structure Therapeutics — The biotech company’s shares soared 60% after positive results from a midstage clinical trial showed its experimental anti-obesity drug helped patients lose about 6% of their starting weight after 12 weeks of treatment. Autodesk — The software company rallied 5% after saying it would not restate financial results following an investigation into its accounting practices. Krispy Kreme — Shares of the company rose 2% after it was upgraded to overweight at JPMorgan. The firm thinks increased accessibility will allow the company to more fully participate in the global indulgence market. McDonald’s and Krispy Kreme previously announced in March that they are expanding their partnership to all of the burger chain’s U.S. locations by the end of 2026. Masimo — The health technology stock popped 2% on the back of Piper Sandler’s upgrade to overweight from neutral. Piper Sandler said investors have a better chance than not for making money on the stock with where it currently trades. MongoDB — The developer data platform traded higher by 1% on the heels of a Guggenheim upgrade to neutral from sell. Guggenheim’s call comes after the company offered weak guidance for the current quarter and full year to investors last week. First Solar — Shares increased 1% following Goldman Sachs’ reiteration of the solar solutions company as a buy. Goldman said there are multiple reasons to stay optimistic on share performance, even after a recent runup. — CNBC’s Sean Colon, Yun Li, Pia Singh, Michelle Fox and Christina Cheddar-Berk contributed reporting.