Substantial T. Rex auction at Sotheby’s raises fears that hype and wealth are turning upside down Science

Forget about selling century. Sotheby’s auction house is preparing for a period sale. Live bidding on various fossils will begin on July 14, but the pièce de résistance is lot 20, a occasional specimen dating back 67 million years Tyrannosaurus rex skeleton.

The specimen – named Gus – is touted as one of the largest and most complete T. rexes ever found. Gus is expected to fetch up to $30 million and will go to the highest bidder, whether a public museum or a private collector. The latter are playing an increasingly crucial role in the purchase of fossils, and auction houses, according to paleontologists, contribute to this trend by building buzz. But when private collectors step in and buy fossils at auction as luxury assets, these sciences actually lose these pieces of history.

By almost every measure, Gus is a huge deal. In its description, Sotheby’s boasts that the specimen discovered on a South Dakota ranch contains “an incredible 183 fossilized bone elements,” meaning it is “approximately 61% complete based on bone count.” The fossilized remains were embedded in a custom steel armature along with replicas of the missing bones. The result is a reconstructed skeleton posed as if in pursuit, with a mouth full of dagger teeth, ready to tear its prey to pieces.

“It really does seem like a spectacular specimen,” says Thomas Holtz, a tyrannosaur specialist at the University of Maryland. The completeness of the skeleton and the high quality of the bones make Gus “of scientific significance,” he says.

Gus is the latest enormous dinosaur fossil to be auctioned in the US. This trend began in earnest in 1997, when Sotheby’s auctioned the most complete Sue T. rex registered. This specimen sold for approximately $8.4 million – the most ever paid for a fossil at auction.

“Before Sue was sold, there were no laws about who owned fossils. There wasn’t really any value assigned to them,” says Cassandra Hatton, vice president and head of science and natural history at Sotheby’s. In many other countries, fossils are state property. However, the legal cases surrounding Sue have made it clear that in the US, anyone who owns land also owns any fossils found on it, Hatton explains. Since then, the market has been booming.

But while Sue was visiting a scientific institution – the Field Museum in Chicago – in recent years ultra-wealthy people have been buying dinosaur fossils at auction for their private collections, prompting paleontologists to worry about the fate of the occasional specimens. Technology entrepreneur Dan O’Dowd owns the company T. rex called Samson. And he’s not the only private collector who owns the tyrant lizard king. A study published in 2025 found that more fossils exist T. rex in private collections than in public funds.

It’s not only that T. rex it ends up in personal files. In 2024, Sotheby’s sold Stegosaurus assigned Apex to billionaire hedge fund Ken Griffin for a record $44.6 million. And last year, an auction house sold the only known minor Ceratosaurus in the world to an anonymous buyer for $30.5 million. These examples highlight another trend: as prices rise, museums simply cannot compete at auctions.