On Thursday, Genesis Global Capital and crypto exchange Gemini were charged by the SEC with offering and selling unregistered securities to retail investors. The regulator maintained that the program the two firms collaborated on, which promised customers high rates of return on deposits in return for allowing them to be loaned out to other entities, was actually an unregistered security under the law.

The Securities and Exchange Commission claimed that Genesis and Gemini, which was founded by Tyler and Cameron Winklevoss, used unregistered offers to raise billions of dollars in cryptocurrency assets from hundreds of thousands of investors. The regulator maintained Gemini’s earn crypto asset-lending program bypassed, “disclosure requirements designed to protect investors.”

In a statement, SEC Chair Gary Gensler said, “Today’s charges build on previous actions to make clear to the marketplace and the investing public that crypto lending platforms and other intermediaries need to comply with our time-tested securities laws. Doing so best protects investors. It promotes trust in markets. It’s not optional. It’s the law.”

The complaint noted that under the Earn program which Gemini and Genesis partnered on, customers of Gemini were allowed to loan their assets to Genesis in return for high interest payments.

According to the SEC Gemini facilitated the program, and would draw off an agent fee of as much as 4.29% from the returns it received from Genesis.

In November, following the collapse of the now-defunct cryptocurrency exchange FTX, to which Genesis had exposure, the lender claimed it was suffering from a liquidity crunch, and froze withdrawals. Approximately 340,000 customers were left unable to withdraw roughly $900 million in cryptocurrency assets.

Gurbir S. Grewal, the director of the SEC’s Division of Enforcement, said, “The recent collapse of crypto asset lending programs and the suspension of Genesis’ program underscore the critical need for platforms offering securities to retail investors to comply with the federal securities laws.”

The complaint from the regulator seeks to see any “ill-gotten gains” returned to investors with interest, as well as civil penalties.