Another startup focused on a buzzy derivative popular among crypto traders has attracted serious cash. Ostium, a decentralized exchange founded by two Harvard graduates, has raised a $20 million Series A round led by the marquee venture outfit General Catalyst and the crypto arm of the quantitative trading firm Jump Trading, Kaledora Kiernan-Linn, cofounder and CEO, told Fortune.
Ostium lets users bet on real-world assets like stocks, metals, oil, and some cryptocurrencies. Traders can take on higher risk through perpetual futures. Unlike traditional futures, these derivatives don’t expire on a set date—assuming traders maintain the necessary margin requirements.
Other participants in fundraise included Coinbase Ventures as well as the crypto market making firms Wintermute and GSR. The round valued the startup at about $250 million, according to a source familiar with the matter, who asked for anonymity to discuss private business dealings. Ostium had previously raised a total of about $8 million.
“We live in a world where traditional financial institutions and financial products still have a lot of relevance, but at the same time, there’s this growing group of consumers and this growing asset class in crypto,” Marc Bhargava, managing director at General Catalyst, told Fortune. “How do we fuse the two?”
Perpetuals party
With 15 employees, Ostium is the latest startup to join an increasingly crowded field of decentralized exchanges that let users trade perpetuals, or “perps.” Although crypto founders have tried for years to build “perps” exchanges, enthusiasm for the derivatives reached a new high after the trading protocol Hyperliquid grew in 2025 to challenge some of the largest crypto trading platforms in the world, even Binance. Soon, perpetuals startups like the Peter Theil-backed Lighter and the Binance-associated Aster rose to challenge Hyperliquid.
Ostium, a reference to the ancient Roman port city of Ostia, doesn’t aim to compete with these trading protocols, which Kiernan-Linn compared to traditional stock exchanges. “We want to compete with the Robinhoods, the eToros, the IGs of the world,” she said, referring to online brokerages.
And Kiernan-Linn believes her background as a classical ballet dancer gives her a leg up. “Ballet is really tough,” she said. “Old school, like Soviet teachers, very exacting. French women who grew up under a very different environment.”
When she was a teenager, she nabbed a spot in The Royal Danish Ballet. She danced there for four years before she finished out her degree at Harvard University, where she met her cofounder Marco Antonio Ribeiro, a former competitor in the International Olympiads for physics, biology, and chemistry.
The two stayed in touch, and in 2022, they founded Ostium. As opposed to Hyperliquid or Lighter, which first focused on letting users trade perpetual contracts for cryptocurrencies, Ostium has focused on tangible assets like metals and energy. While the trading protocol has so far targeted crypto-native users wanting to play in traditional markets, Kiernan-Linn and her cofounder Ribeiro plan to use their startup’s recently raised stash of $20 million to target non-crypto users outside the U.S.
“Where we are actually going after is the offshore broker market,” she said. In other words, she plans to target non-U.S. investors who want access to U.S markets. These traders have to wade through an opaque system of brokers and slow technology, which she believes Ostium can disrupt. “There’s really very, very few people building in the space at all, or certainly not talking about it in crypto,” she said. “And it is a textbook use case for blockchain.”
