Seth Klarman
Seth Klarman.
  • Seth Klarman's Baupost has likely made a $190 million gain on Warner Bros. Discovery this year.
  • The billionaire investor's hedge fund built a 1.3% stake worth almost $300 million last year.
  • "Hogwarts Legacy" has boosted WBD stock, lifting Baupost's stake to nearly $500 million on paper.

Seth Klarman's Baupost Group has likely scored a nearly $200 million gain on Warner Bros. Discovery since the start of this year. The hype around "Hogwarts: Legacy" has helped propel the media stock up 65% over the past two months, meaning WBD rivals Tesla as the S&P 500's best performer so far this year.