Ken Griffin's Citadel boosts stake in James Dolan's Sphere weeks after Steve Cohen's investment

Ken Griffin's Citadel has boosted its stake in James Dolan's Sphere Entertainment just weeks after another hedge fund titan, Mets owner Steve Cohen, revealed that he invested in the company. Sphere shares ticked down less than 1% Thursday, trading at $43.45. Citadel and Sphere Entertainment both declined to comment. 4 Sphere Entertainment owns and operates Sphere, the mammoth concert venue in Las Vegas. Getty Images Getty Images 4 The Dolan family has voting control of Sphere Entertainment. Dolan, the son o ...