The U.S. Securities and Exchange Commission has threatened to sue Coinbase ($COIN@US) if the crypto exchange goes ahead with plans to launch a program allowing users to earn interest by lending crypto assets. The SEC has issued Coinbase a Wells notice, an official way it tells a company that it intends to sue the company in court. Coinbase plans to delay the launch of its Lend product until at least October as a result. Coinbase shares fell about 2.5% to $260 in pre-market trade on Wednesday. Programs that allow owners of cryptocurrencies to lend these in return for interest are becoming more common worldwide. Still, some regulators, particularly in the United States, have started to raise concerns, arguing that such products should comply with existing securities laws. In July, New Jersey ordered the cryptocurrency platform BlockFi to stop offering interest-bearing accounts. The SEC's concerns about Coinbase's Lend program are related to the fact that the regulator believes that the product is a security, but Coinbase feels that this is not the case. Regulators in the U.S. have been increasingly concerned over cryptocurrencies that they believe meet the definition of a security. Coinbase, Ripple, and BlockFi have all faced legal orders or notifications from the SEC regarding their respective offerings.