Hedge fund billionaire Ken Griffin, founder and CEO of Citadel, has been revealed as the buyer of the record-setting "Apex" Stegosaurus skeleton at a Sotheby's auction yesterday.  

Griffin purchased the fossil, billed by Sotheby's as "the finest to ever come to market," for almost $45 million, a record, a person familiar with the matter told CBS MoneyWatch. The sale price far exceeds the estimate of $4 million to $6 million that Sotheby's had assigned to the lot. 

Described as a mounted Stegosaurus skeleton, the exact sale price was $44.6 million, marking a new record for dinosaur fossils. 

Griffin plans to explore loaning the specimen to a U.S. institution, and wants to share it with the public, as opposed to hanging it as a trophy exclusively for private viewing.

"Apex was born in America and is going to stay in America!" Griffin said following the sale, according to a person familiar with the matter. 

In 2017, Griffin underwrote an historic dinosaur exhibit at the Field Museum in Chicago, Illinois, with a $16.5 million gift to support its acquiring Sue the T. rex, a 122-foot-long Tyrannosaurus rex.

"The Field Museum's never-ending goal is to offer the best possible dinosaur experiences. Ken Griffin's long-time support is a major step forward in achieving that goal," Field Museum president Richard Lariviere said at the time. "With this extraordinary gift from Ken, we'll be able to create a more scientifically accurate and engaging home for Sue the T. rex and welcome the world's largest dinosaur to the Field."

Griffin intends to keep "Apex" stateside after the government of Abu Dhabi purchased "Stan," a male Tyrannosaurus rex, for nearly $32 million, and moved it to a new natural history museum there.

After the sale Wednesday, Sotheby's, which had kept the buyer's identity under wraps, said Apex was "chased by seven bidders" during the live auction. 

"'Apex' lived up to its name today, inspiring bidders globally to become the most valuable fossil ever sold at auction," Cassandra Hatton, Sotheby's Global Head of Science & Popular Culture, said in a statement Wednesday. "I am thrilled that such an important specimen has now taken its place in history, some 150 million years since it roamed the planet. This remarkable result underscores our unwavering commitment to preserving these ancient treasures." 

In:
• Sotheby's
• dinosaur

Megan Cerullo

Megan Cerullo is a New York-based reporter for CBS MoneyWatch covering small business, workplace, health care, consumer spending and personal finance topics. She regularly appears on CBS News 24/7 to discuss her reporting.