Facing intense legal scrutiny, Mr. Zhao, 47, who goes by the initials CZ, was often dismissive. He described the concerns about Binance as “FUD,” or fear, uncertainty and doubt — shorthand in the crypto world for false rumors intended to hurt a business.

In November 2022, Mr. Zhao’s industry power increased after he helped bring down Mr. Bankman-Fried with a series of social media posts that prompted a run on FTX’s accounts. When FTX didn’t have the money to repay its customers, Mr. Zhao briefly agreed to buy the exchange, before pulling out of the deal. Soon Mr. Bankman-Fried was arrested on fraud charges.

A year later, it was Mr. Zhao’s turn to face criminal prosecution.

In November, Binance agreed to pay $4.3 billion to several U.S. agencies, including the Justice Department, to settle charges that it had permitted terrorist organizations like Hamas, the Islamic State and Al Qaeda to use its platform. Prosecutors said that, under Mr. Zhao’s watch, Binance had refused to comply with American sanctions, allowing access to customers in countries like Iran, Syria and Cuba. The company also failed to report suspicious transactions involving narcotics and child sexual abuse materials, the government said.

Mr. Zhao told Binance employees that it was “better to ask for forgiveness than permission,” prosecutors said in a recent court filing. He also bragged that if Binance had complied with U.S. law, it would not be “as big as we are today,” the prosecutors wrote.

In the end, Mr. Zhao pleaded guilty to a single criminal count, admitting that he had failed to establish an adequate anti-money-laundering system at Binance. He also resigned as chief executive and agreed to a $50 million fine. He has a $33 billion fortune, according to Forbes, making him crypto’s wealthiest executive.