Gemini, a crypto exchange run by billionaire twins Tyler and Cameron Winklevoss, on Friday disclosed it had confidentially filed for a U.S. initial public offering, as digital asset firms seize on renewed market momentum.

Circle closed with an $18.4 billion valuation, well below Coinbase’s IPO but ahead of newer entrants like Fold and eToro.

Founded by the Winklevoss twins, Cameron and Tyler, in 2014, Gemini is one of the longest-operating U.S. crypto companies, though it has never reached the scale of competitors like Coinbase. Though Gemini’s main product is its exchange,