A juvenile Ceratosaurus from Wyoming’s Bone Cabin Quarry hit the Sotheby’s auction block with a value of $6 million. After six minutes of bidding, it sold for $30.5 million.
An as-of-yet unknown buyer acquired the one-of-a-kind dinosaur specimen on July 16. Even Brock Sission, the commercial paleontologist who put the specimen up for auction, doesn’t know who bought it – or how much he’ll see from the $30.5 million sale.
“After commissions, premiums from the auction house, and all the stuff that goes along with it, I don't know how much I'll end up with,” he told Cowboy State Daily. “I think it’ll be a lot, but I don’t know what it’s going to be.”
For Sisson, it’s a full-circle story with a specimen that left a big impact on him from the first time he beheld it. Nevertheless, he hopes the story for this one-of-a-kind dinosaur isn’t over and, if he can, hopes to ensure it “finally gets the attention it deserves.”
One Of A Kind
Ceratosaurus is a rare and unusual dinosaur. The juvenile specimen sold at Sotheby’s was one of only four known skeletons of this carnivore from the Late Jurassic Period of North America.
Unlike its contemporary Allosaurus, Ceratosaurus exhibits several distinct features, including a bony horn at the end of its snout, four fingers on each hand, and a row of armor-like bones, known as osteoderms, covering its back.
This Ceratosaurus was discovered in Bone Cabin Quarry, one of the most renowned and significant fossil sites in the world, located near Medicine Bow, Wyoming.
It was first discovered and excavated by the American Museum of Natural History in New York City, and continues to be a goldmine of significant fossils from the Late Jurassic Period.
The 11-foot-long specimen, which included a remarkably complete skull, a complete pelvis, and several other bones, was excavated by Western Paleontological Laboratories in 1996. It was in the collections of the North American Museum of Ancient Life at Thanksgiving Point in Lehi, Utah, until 2024.
Sisson first encountered the specimen when he was a 16-year-old employee working with Western Paleontological Laboratories.
“I was carrying the boxes with the bones into the museum,” he said. “It’s one of the first original dinosaurs I ever got to work with, and it’s always been one of my favorite types of dinosaurs and my favorite individual dinosaur specimen. It left a big impression.”
For the next 25 years, the Ceratosaurus was displayed and unstudied at the Museum of Ancient Life. Since it wasn’t receiving much attention, Sission approached the museum’s board with an offer to purchase the specimen from the museum.
In 2024, the museum board agreed to sell the Ceratosaurus to Sisson, and he prepared the specimen for auction at Sotheby’s.
“It was an opportunity that presented itself, and so I took advantage of it,” he said.
A Mounted Juvenile Ceratosaurus Skeleton, Late Jurassic, Kimmeridgian Stage (Sotheby's Auction) 
A Mounted Juvenile Ceratosaurus Skeleton, Late Jurassic, Kimmeridgian Stage (Sotheby's auction) 
A Mounted Juvenile Ceratosaurus Skeleton, Late Jurassic, Kimmeridgian Stage (Sotheby's auction) 
A Mounted Juvenile Ceratosaurus Skeleton, Late Jurassic, Kimmeridgian Stage (Sotheby's auction)
Millions of Years, Millions of Dollars
Sotheby’s is where the dinosaur auction market originated. In 1997, “Sue,” the most complete Tyrannosaurus specimen ever found, was sold at auction for $7.6 million to the Field Museum in Chicago, Illinois.
In 2020, another Tyrannosaurus specimen, “Stan,” sold for $31.8 million at a Christie’s auction. That specimen will be the centerpiece of a paleontological display at the Natural History Museum Abu Dhabi in the United Arab Emirates.
Despite being a fraction of the size of Stan, the juvenile Ceratosaurus sold for almost the same amount. Sisson views it as a sign of the incredible potential in the dinosaur market.
“There’s no price guide for a Ceratosaurus,” he said. “We know how much Sue sold for 25 years ago, and what Stan sold for five years ago. An auction is a good way to find out what a Ceratosaurus is worth.”
The Ceratosaurus ultimately became the third highest-selling dinosaur at auction, behind Stan and Apex, a Stegosaurus specimen that sold at sold at Sotheby’s for $44.6 million in July 2024.
Wyoming dinosaurs are becoming increasingly common at auction. A Tyrannosaurus partially composed of Wyoming fossils sold for a "disappointing" $5.3 million at an auction in Zurich in April 2023, a Camptosaurus from Crook County was auctioned in Paris in September 2023, and a trio of Jurassic dinosaurs - a Stegosaurus and two Allosaurus - sold for $15 million at Christie's in London in December 2024.
Multi-million-dollar dinosaur auctions are the worst-case scenarios for many paleontologists. The Ceratosaurus auction was especially egregious to many, given that it was a rare specimen that had been sold by a museum that had curated it for over two decades.
Sisson said he hasn’t received much negative feedback about the auction, and the Museum of Ancient Life was perfectly within its rights to sell the specimen.
“The museum wasn't a recognized federal repository,” he said. “That's one of the reasons that no scientific work has been done on this specimen for the last 25 years. (Paleontologists) wanted it to be at a different kind of museum before they studied it. So, the specimen's status didn’t change when I purchased it. It was still privately held, just not on public display.”
Now that the auction has concluded, the specimen remains privately held and is not on public display. It’s too early to say when or if it will resurface in the future.
Science Vs Sales
Some news agencies have stated that, post-auction, one of the conditions of the sale was that the specimen be made available for research and display in a public museum. Sisson noted that this isn’t true.
“There were no conditions to the sale,” he said. “It sounds like the new owner, whoever that may be, is interested in putting it on loan at a museum. It may already be a museum, but I don’t have any details on that yet.”
Kenneth Griffin, the billionaire who acquired Apex, loaned the specimen to the American Museum of Natural History in New York City for a period of four years, during which it will be available to paleontologists and the public. However, it is a temporary loan rather than an outright donation.
The Society of Vertebrate Paleontologists (SVP) sent a letter to the American Museum of Natural History, stating that it “strongly opposes” the museum's plans for the privately owned specimen. They say it “sets a dangerous precedent by legitimizing private ownership of vertebrate fossils.”
“Scientific reproducibility is a core principle of SVP’s Code of Ethics,” the letter reads. “In paleontology, reproducibility requires that scientists other than those conducting the original research have access to the same fossil specimen(s). To ensure this access, fossils must be held in (or destined for) collections in institutions committed to their permanent care and accessibility.”
A New York Times article following the sale said the owner intends to loan the Ceratosaurus to a museum, but that won’t be enough to assuage the fears and anger of paleontologists. SVP would likely send a similar letter to any museum that accepts the specimen on temporary loan.
The Museum of Ancient Life has also come under scrutiny for profiting from the sale of a specimen that had been curated in their collection for decades. Paleontologists have expressed their outrage by vowing to avoid any future collaboration with the museum.
McKay Christensen, the chief executive of Thanksgiving Point, told the New York Times that the board “unanimously approved” the sale of the specimen to Sisson, a “longtime trusted friend and partner to the museum,” and the money they received will be used to “protect our collections, educate visitors, and further expand our collections.”
Paleontologists worry that a private museum selling an accessioned specimen sets a worrying precedent for the future, where fossils are viewed as assets for sale rather than as tools for scientific research. For his part, Sisson said he doesn’t plan on “making a habit” out of buying specimens from museums for auctions.
“This wasn’t part of my business model,” he said. “I have three quarries where I dig Jurassic dinosaurs, and a pretty good supply of dinosaurs that I can prepare and sell. There’s no reason to go through the arduous process of deaccessioning and all the things we ended up doing to make this sale possible.”
For Scientific Scrutiny
Sisson’s company, Fossilogic, has been selling real and replica dinosaur fossils and skeletons to museums worldwide for decades. They were selling replicas of the juvenile Ceratosaurus before the auction, but now that it has been sold, they won’t be selling any more.
“I sold it with complete intellectual property rights,” he said. “The buyer has all the duplication and research rights. Everything was included to keep it as one unit, rather than having it parted out.”
Sisson hopes to eventually connect with the buyer to facilitate the creation of more replicas and further research. Of course, he’d have to learn the buyer's identity first.
Bone Cabin Quarry is currently owned by Wyoming Dinosaur Discovery LLC, founded by Thomas Lindgren and Jeffrey Parker, the paleontologists who found the juvenile Ceratosaurus in 1996. They sold 40,000 shares of a 70% complete Stegosaurus specimen they’ve discovered at the site, which will be sold at auction in the near future.
Amidst the controversy of high-priced dinosaur auctions and the private ownership of significant fossils, Sisson said he’s always tried to work in the best interests of museums and paleontologists.
“I do a lot of stuff behind the scenes,” he said. “We work on quite a few scientific papers, recently published papers naming new species of dinosaurs, and have donated quite a few specimens to museums.”
Sisson says one of his reasons for sending the juvenile Ceratosaurus to auction was to increase its chances of contributing to the science of paleontology. Its monetary value was determined at auction, but its scientific value has been untapped for decades.
“We did try very hard to make scientific institutions aware of this specimen,” he said. “My goal all along was to get this into a scientific repository where it can be studied. Through the attention and publicity, it might finally receive some of the scientific work that it really needs.”
Sisson says he intends to “reinvest in the science” with his cut of the proceeds from the Sotheby’s auction. And, if he can advocate for the future of the $30-million, 145-million-year-old baby Ceratosaurus, he certainly will.
“It's a cool specimen that we can learn a lot from, and I think we are much closer now than we have been since it was found to getting that science done,” he said.
Andrew Rossi can be reached at arossi@cowboystatedaily.com.
