He is on the board of the Whitney Museum of American Art, which named the lobby of its new building after him. He donated $40 million to the Museum of Modern Art. Mr. Griffin and his ex-wife donated $19 million to the Art Institute of Chicago. And at the Field Museum of Natural History in Chicago, Mr. Griffin donated $16.5 million to fund the purchase of a cast of Patagotitan mayorum,the largest dinosaur ever discovered.

Mr. Griffin has also donated huge sums to educational institutions.

In 2014 he gave $150 million to Harvard University, at the time, the largest gift in the school’s history. In 2017 Mr. Griffin’s charity said it would donate $125 million to the University of Chicago, which would rename its influential department of economics after him. More recently, Mr. Griffin has turned his acquisitive eye toward real estate.

Fellow financiers said Mr. Griffin should be applauded for his philanthropy, rather than vilified for his spending. John W. Rogers Jr., the chief executive of Ariel Investments, who serves on the board of the University of Chicago with Mr. Griffin (as well as on the board of The New York Times Company), declined to comment on his real estate spending. “The key thing is that he’s decided to be generous now,” Mr. Rogers said. “Ken is a role model for the next generation of hedge fund managers.”

Mr. Griffin has cited his maternal grandparents as inspiration for his philanthropy. They ran a fuel oil business in Illinois, and when some customers could not pay their bills during the winter, his grandparents would extend them credit.

The Harvard graduate made his fortune through finance. As a sophomore in 1987, Mr. Griffin began trading out of his dorm room using a fax machine, an early personal computer and the phone. Just three years later, he founded Citadel in Chicago.

The firm grew rapidly, and today Citadel, which is privately held, manages some $28 billion, trading stocks, fixed income, commodities and more.