Michael Saylor’s big bet on Bitcoin was supposed to be his downfall. Instead, it has helped him reap a huge windfall from his holdings in the cryptocurrency and in MicroStrategy stock.

So far this year, the billionaire executive chairman of MicroStrategy has made $370 million by selling hundreds of thousands of company shares through a stock-sale plan struck with the company last year, according to filings with the Securities and Exchange Commission.

But that doesn’t include his massive paper profits. As of Friday, the combination of Saylor’s total MicroStrategy shares (excluding those in the stock-sale plan) and his last revealed count of personal Bitcoin were worth approximately $3.49 billion. Since the start of this year, that’s a gain of about 60%, or upwards of $1 billion. And since the start of 2023—when the crypto sector began rebounding—his shares and Bitcoin holdings have given him approximate paper gains of just under $3 billion.

The value of MicroStrategy’s stock has exploded since January as Bitcoin soared to new highs in part due to the launch of new exchange-traded funds that track the token. MicroStrategy’s shares are up 86% after soaring more than 300% in 2023. Shares closed down 2.8% at about $1,174 on Friday. Meanwhile, Bitcoin is up 46% in 2024 and has leapt nearly 300% since the start of 2023.

Saylor, the once-crypto skeptic turned believer, has made MicroStrategy into a proxy for Bitcoin’s success. Over the past four years, the company bought up billions of dollars worth of the token, sometimes using leverage. While he was CEO in 2020, Microstrategy bought its first Bitcoin tokens—spending $250 million to buy 21,454 at an average price of about $12,000 each.

Four years and multiple purchases later, MicroStrategy owns more than 214,000 Bitcoin, about 1% of all tokens in circulation. At Saturday's price of about $64,000 per Bitcoin, MicroStrategy’s holdings are worth about $13.7 billion. Because Saylor owns about 12% of the company’s shares, his stock holdings plus his personal stash of more than 17,000 Bitcoin factor in majorly to his net worth of just under $4 billion, according to Forbes.

MicroStrategy did not immediately respond to Fortune’s request for comment.

But Saylor hasn’t always been this lucky. After he became a billionaire through MicroStrategy during the dot-com boom, Saylor faced his biggest obstacle. In 2000, MicroStrategy disclosed that its revenue from 1999 was 25% less than it had originally claimed. The accounting scandal cost him $6 billion in one day—the most any single person had ever lost in the span of 24 hours up to then. The SEC accused him of violating federal securities laws later that year, and he settled the charges, paying $8 million to the agency without admitting wrongdoing.

Later, Saylor’s Bitcoin moves were also seen by investors and analysts as crazy. At least one analyst, David Trainer of research firm New Constructs, told Fortune in 2022 that Saylor was “grossly misallocating his investors’ capital,” with his Bitcoin purchases.

“In terms of madmen, Saylor is ‘Elon Junior,’ without the business talent,” Trainer said at the time.

For a while it seemed as if the naysayers were right. After making a killing for MicroStrategy (at least on paper) when Bitcoin hit its previous high point in November 2021, the company’s approach backfired when Bitcoin prices plummeted. MicroStrategy was one of the worst performing large-cap stocks of 2022, largely because of falling Bitcoin prices.

Still, Saylor never wavered in his dedication. Last month, Saylor told CNBC that Bitcoin was “going to eat gold,” replacing it as the most common store of value.

It may still be too soon to tell how MicroStrategy’s plan to be the go-to proxy for Bitcoin will fare, especially after several spot Bitcoin ETFs meant to do the same thing were approved by the SEC in January.

Yet Saylor, with his newly minted millions, isn’t worried in the slightest.

“Is there any company in the world that you wouldn’t like to invest in that could borrow $1 billion at less than 1% interest to invest in your best idea?” he told CNBC.