Ken Griffin, who runs a sprawling Wall Street empire that includes market making operations and a hedge fund, was dismissive of cryptocurrencies even as some see the emerging asset as the future of finance.

“I just don’t spend much time thinking about cryptocurrencies … I don’t see the economic underpinning of cryptocurrencies. I understand how to value a stock — the net present value of earnings — I understand how to think about currency exchange rates around the world,” Griffin said to Andrew Ross Sorkin on CNBC’s “Squawk Box.” “I don’t know how to think about what is effectively a digital token.”

Bitcoin has soared in recent months, boosted in part by adoption from major financial institutions, investors and companies, including Tesla. Employees and customers of major Wall Street banks are also pushing for greater involvement in cryptocurrencies.

Bank of New York Mellon, the oldest U.S. bank, said earlier this month that it would begin financing bitcoin and other digital currencies.

Citadel Securities is market maker that handles about 40% of the daily retail trading in the United States, making it one of the biggest companies involved in the nation’s financial plumbing. Griffin also founded a hedge fund named Citadel.

Bitcoin was trading above $52,000 per coin on Friday, according to Coin Metrics, putting its six-month gain at more than 330%.

Griffin’s comments came as part of an interview regarding Citadel’s role in the GameStop saga. The firm handled retail trades from discount brokerage Robinhood during