Hedge-fund billionaire Ken Griffin bought the fossil ... one of the few Stegosaurus specimens ever found that appeared to live to an advanced age. Griffin snapped up the specimen in an intense ...

Billionaire investor Ken Griffin's flagship hedge fund climbed in a volatile January, according to a person familiar with the returns. Citadel's multistrategy flagship Wellington fund rose 1.4% ...

Citadel’s Ken Griffin is forging ahead with his new Park Avenue office tower, filing plans with the city as the developers ...