NEW YORK – Former cryptocurrency billionaire Sam Bankman-Fried knowingly stole money from customers of his FTX platform, US prosecutors told a federal court in closing arguments on Wednesday.

“This is not about complex issues of cryptocurrencies,” prosecutor Nicolas Roos told the jury after several days of whithering cross-examination of the fallen crypto king.

“It’s about deception. It’s about lies. It’s about stealing. It’s about greed,” he said of the 31-year-old who was estimated to be worth several billion dollars at the height of his fame.

Bankman-Fried is on trial in New York for siphoning funds invested by unknowing customers on his FTX cryptocurrency exchange platform, once the second-biggest exchange for crypto investors.

He faces decades in prison if convicted.

Up to US$14 billion (S$19.2 billion) of client money fuelled the transactions and venture investments of Alameda Research, Bankman-Friend’s personally owned hedge fund.

The jury is faced with the question whether “the defendant knew taking the money was wrong”, Mr Roos said.

“He knew it was wrong. He did it anyway (and) thought because he was smart he could get away with it,” the prosecutor argued.

To believe otherwise, “you’d have to believe that the defendant was actually clueless”.

“You sat through this trial and you know that none of it is true.”

During the trial that began on Oct 3, the Massachusetts Institute of Technology graduate admitted he made “mistakes” in managing his crypto empire, but that he never committed fraud.

He depicted himself as a young entrepreneur swamped with work who became aware of the trouble at Alameda only when it was too late.

He said the problems at Alameda arose because his directions were ignored by staff, including his former girlfriend Caroline Ellison, whom he had tapped to run Alameda.

Mr Roos pointed out that three witnesses, Ellison and other close associates, each claimed that the former cryptocurrency genius had given instructions for Alameda to pilfer the coffers of FTX, virtually without limit.

“That’s fraud. That’s stealing, plain and simple,” Mr Roos said.

The trial has revealed that company software authorised Alameda to borrow up to US$65 billion from FTX via a “back door”, using the money for risky investments, political donations and the purchase of swishy real estate.

But the blank cheque turned sour when the cryptocurrency industry was rocked by a series of defaults in 2022, causing the value of virtually all digital currencies and Alameda’s assets to plummet.

According to prosecutors, at the time of the bankruptcy of FTX, just over US$8 billion belonging to customers vanished into bad investments at Alameda. AFP