Gary Gensler, Chair of the U.S. Securities and Exchange Commission, takes his seat before the start of the Senate Banking, Housing, and Urban Affairs Committee hearing on Oversight of the U.S. Securities and Exchange Commission on Tuesday, Sept. 14, 2021.

Bill Clark | CQ-Roll Call, Inc. | Getty Images

SEC Chair Gary Gensler stepped up his attack on the crypto industry this week, suing Coinbase and Binance for securities violations and casting doubt on the future of token trading.

Crypto investors took the hint. Four of the 10 most valuable coins plunged in value by at least 15% this week, according to CoinMarketCap, a sell-off sparked by the lawsuits and Gensler’s interview with CNBC on Tuesday, in which he said “we don’t need more digital currency.”

In alleging that Coinbase was acting as an unregistered broker and exchange, the Securities and Exchange Commission said at least 13 crypto assets available to the company’s customers were considered “crypto asset securities.” They include Solana’s SOL token, Cardano’s ADA token, Polygon’s MATIC coin and Protocol Labs’ Filecoin token (FIL).

Trading app Robinhood followed on Friday by announcing that, starting June 27, it will no longer support trading of coins from Cardano, Polygon and Solana. The company said “no other coins are affected.” Also on Friday, Crypto.com said it will shut down its U.S. institutional exchange.

“No other coins are affected and your crypto is still safe on Robinhood,” the company said in a post.

Cardano’s coin, the seventh-most valuable cryptocurrency, according to CoinMarketCap, tumbled 20% in the past week. Solana, ranked ninth, dropped 18%. Polygon, ranked 10th, also slid 18%. Filecoin, which is further down the list, dropped 19%. Binance’s BNB token, ranked fourth, fell 16%.

Bitcoin and ethereum, the two most popular cryptocurrencies, were more stable, each declining less than 5%.

Gensler, who was appointed to head the SEC by President Joe Biden in 2021, has spent much of the past year going after crypto firms and exchanges for effectively selling highly speculative and risky securities dressed up as something else.

From high-profile fraud cases involving Sam Bankman-Fried’s FTX and Do Kwon’s Terraform Labs to dozens of charges involving coin offerings and alleged false marketing, Gensler has made the once-burgeoning crypto industry his primary takedown target.

“The investing public has the benefit of U.S. securities laws,” Gensler said in an interview with CNBC’s “Squawk on the Street” on Tuesday. “Crypto should be no different, and these platforms, these intermediaries need to come into compliance.”

Gensler’s TV appearance came after the SEC sued Coinbase and said the company should be “permanently restrained and enjoined” from “operating its crypto asset trading platform as an unregistered national securities exchange, broker, and clearing agency.”

Shares of Coinbase, the only major crypto exchange that’s publicly traded in the U.S., sank 18% this week. Coinbase legal chief Paul Grewal told CNBC in a statement that the SEC’s approach to enforcement without laying out clear rules is “hurting America’s economic competitiveness and companies like Coinbase that have a demonstrated commitment to compliance.”

A day earlier, in its lawsuit against Binance, the SEC alleged that the company and founder Changpeng Zhao comingled billions of dollars worth of user funds and sent them to a European company controlled by Zhao.

While Binance claims no official headquarters and does most of its business overseas, the SEC’s complaint cited a senior executive allegedly telling a compliance officer that the company was operating as a “[f—ing] unlicensed securities exchange in the USA bro.”

In a blog post, Binance said it was “disappointed” in the SEC’s suit and said it had “engaged in extensive good-faith discussions to reach a negotiated settlement to resolve their investigations.”

Others named in the SEC lawsuit also weighed in after this week’s charges landed.

The Cardano Foundation, which works to advance use of its namesake technology, said in a tweet that it disagrees with the labeling of its ADA coin as a security and “we look forward to the continued engagement with regulators and policymakers to achieve legal clarity and certainty on these matters.”

Protocol Labs, the developer of Filecoin, said in a series of tweets on Thursday that the token is critical to the operation of its distributed storage network. It’s how people buy storage from providers, and Protocol says the cost is much less than what users would pay Amazon Web Services or Google Cloud.

“Filecoin is a cryptocurrency-powered global storage network preserving humanity’s most important information, not a security,” Protocol Labs tweeted.

In its 101-page complaint against Coinbase, the SEC made clear that regardless of whether these tokens have some level of utility, they can easily be purchased on the app by people who have no interest beyond investing. And Coinbase generates revenue by executing those trades.

“Coinbase makes these crypto assets available for trading,” the SEC said, “without restricting transactions to those who might acquire or treat the asset as anything other than as an investment.”

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