New York CNN  —  Shares of online pet products retailer Chewy went on a wild ride Monday after Keith Gill, the influential meme stock trader also known as ”Roaring Kitty,” revealed a large stake in the company. On Monday, Gill said in a Securities and Exchange filing that he purchased about 9 million Chewy shares (CHWY), amounting to a 6.6% stake in the company. Chewy shares slipped about 5% mid-morning on Monday after jumping as much as 10% earlier in the session. Chewy shares began gaining last Thursday after Gill, the individual investor who helped spark the frenzied trading around GameStop shares three years ago, posted a photo of a cartoon dog on his X account. The cartoon’s blue background appeared to be the same blue as Chewy’s logo. Shares of the company surged more than 34% that day at its highs before closing 0.3% lower. Meme stocks more typically move on social media sentiment than fundamentals, often posting huge swings based on the buying and selling of influential traders like Gill. Ryan Cohen, the founder of Chewy, is the chief executive of GameStop, the embattled video game retailer Gill is known for championing. Keith Gill, a Reddit user credited with inspiring GameStop's rally, during a YouTube livestream arranged on a laptop at the New York Stock Exchange (NYSE) in New York, US, on Friday, June 7, 2024. Michael Nagle/Bloomberg/Getty Images Related article GameStop meme lord behind stock’s wild moves reveals himself after three years Gill revived the meme stock frenzy in May after breaking a three-year social media hiatus to post a cartoon on X. He then posted periodic screenshots of what appeared to be his E*Trade account showing a mammoth position in GameStop shares and options, sending shares of the video game retailer on a wild ride. CNN has not independently verified the screenshots. Last month, Gill revealed that he owns about 9 million shares of GameStop and has exited his huge options position. On Monday’s filing, a question stated: “Check the appropriate box to designate whether you are a cat.” Gill checked the box stating “I am not a cat,” a possible reference to his Congressional testimony about the meme stock frenzy in 2021 when he told the House Financial Services Committee the same statement. That was a nod to a viral moment in a virtual Texas courtroom when a lawyer appeared on the screen with a cat filter.