Crypto exchange Coinbase (COIN) is plunging on Tuesday alongside sharp declines for cryptocurrencies following a Monday night report that the SEC is investigating the company for allowing Americans to trade in tokens that should have been registered as securities. “Coinbase was considered one of the better-run crypto companies that tried to obey the rules and work with the regulatory bodies,” Edward Moya, senior markets analyst at Oanda said in a note Tuesday.

“The risk of tougher regulation has been a constant headache for crypto, and it seems that a couple of tough rulings could cripple a good portion of the cryptoverse," he added. "If some cryptos are deemed securities, that would make the life of so many brokerages so much harder. "While Coinbase is hardest hit, with a 20% drop late on Tuesday afternoon, related players like MicroStrategy (MSTR) and Marathon Digital (MARA) are also suffering sizable declines of roughly 11%.

Checking cryptocurrencies themselves, bitcoin (BTC) – possibly the only crypto the SEC may not deem a security – is outperforming with a 3% decline. Ether (ETH) and Solanas SOL (SOL) are off closer to 7%. "While the digital asset industry was born and grew outside of any real scrutiny by the SEC, that appears to have changed," Tyler Gellasch, executive director of the Healthy Markets Association, told CoinDesk.

"It’s an existential threat to crypto exchanges and brokers, because many of their current revenue streams are either likely dramatically reduced or outright prohibited in the securities world. "Read more: Jefferies Downgrades MicroStrategy to Underperform; Shares Slump.