Better regulation is needed around bitcoin markets before they can be traded on major exchanges, the head of the U.S. Securities and Exchange Commission said on Thursday.

Speaking at CNBC’s Delivering Alpha conference, SEC Chairman Jay Clayton said investors are “sorely mistaken” if they think bitcoin and other cryptocurrencies undergo the same price discovery practices as products on top exchanges like the Nasdaq or New York Stock Exchange.

“We have to get to a place, in my view — just speaking for myself — we have to get to a place that we can be confident that trading is better regulated.”

Clayton said price reports do not indicate thorough price discovery, as he claims major exchanges perform for other financial products. Investor protections built into major exchanges, he continued, are needed in crypto markets before they can be added.

Clayton’s crypto message follows remarks made earlier this month concerning a bitcoin exchange-traded fund (ETF). Clayton claimed there is “work left to be done,” although “progress is being made.”

The financial regulator is nearing deadlines for approving or rejecting bitcoin ETFs from Wilshire Pheonix and Bitwise Asset Management.

A third bitcoin ETF applications, Cboe BZX Exchange VanEck/SolidX bitcoin ETC, was withdrawn earlier this week as an October 18 deadline loomed and approval seemed unlikely.

Jay Clayton image via CoinDesk archives