(Bloomberg) -- Billionaire moneymen Peter Thiel, Alan Howard and Louis Bacon have seen plenty of big paydays—but probably none as unusual as this one.

A buyback by Block.one, a cryptocurrency startup, will return as much as 6,567% to its earliest investors—in less than three years. That translates into $6.6 million for a $100,000 stake, a stunning result any time but especially in a market that crashed in 2018.

“Block.one is very much the odd one out in the crypto market,” said Tom Shaughnessy, co-founder of Delphi Digital, a crypto research firm in New York.

Block.one stands out because of the scope of its ambitions and size of its balance sheet: it raised about $4 billion in the biggest sale of digital tokens. The promise is to help produce key buildings blocks for a new secure version of the internet. The company plans to announce a social-media product in June.

But with few outward signs of progress since the sale of EOS tokens, which was made over the course of a year and wrapped up in June 2018, investors and analysts have had an overriding question: what is 32-year-old Chief Executive Officer Brendan Blumer doing with the money?

“They designed a very clever mechanism to hoover up as much capital as possible”

In a March 19 e-mail to shareholders seen by Bloomberg, the company, which is registered in the Cayman Islands and operates mainly from Hong Kong, disclosed some of the answers: Its assets, including cash and investments, totaled $3 billion at the end of February.

Most of the company’s holdings, $2.2 billion, are in what the e-mail called liquid fiat assets, with the majority of that invested in U.S. government bonds.The e-mail said volatility had “adversely impacted” its cryptocurrency portfolio, halving it to about $500 million. The company held as many as 140,000 Bitcoins, making it one of the largest holders of the original cryptocurrency, according to people familiar with the matter. In an e-mail Tuesday, the company said those losses were “more than fully recovered” as of May 15, as Bitcoin rallied this year.

The firm has so far made $174 million in venture capital investments, either directly or through its partner funds, which include a tie-up with billionaire Mike Novogratz. All along, Block.one has said the money it raised from selling tokens would be funneled to developers building out its EOS platform, including a pledge to allocate $1 billion to venture-capital firms investing in the network.

A spokeswoman for Block.one said the company is using the revenue generated from selling tokens to expand its resources and build its business. She declined to comment on the details of the stock repurchase.

“They designed a very clever mechanism to hoover up as much capital as possible,” said Richard Burton, San Francisco-based founder of Balance.io, a blockchain company that designs applications for open source financial products. “Bitcoin was started on a shoestring and Ethereum raised just a few million dollars, which goes to show you don’t need anything like the money Block.one raised to launch and scale a successful network. It should be beholden on them to explain why they needed that much and what they are doing with it.”

The buyback of 10 percent of its stock values the company at about $2.3 billion, up from about a $40 million valuation in the 2017 seed round. The repurchase price of about $1,500 per share, compared to the $22.50 investors paid in that fundraising. (For context, Uber was valued at about $5 million in a 2010 seed funding and now has a market capitalization of about $70 billion after its initial public offering.)

Thiel, Bacon and Howard bought into the company in July 2018. Bacon and Howard declined to comment on whether they would tender their shares in the buyback. Thiel didn’t respond to multiple messages.

An earlier backer, fintech investor Christian Angermayer, doesn’t intend to sell any shares. “Block.one is one of the most promising and best positioned companies in the blockchain industry, and its success story is just beginning,” he said in e-mailed comments. In a statement Tuesday, Novogratz cited “substantial outperformance” by Block.one for the decision to sell most of his shares. His investment firm reported a 123 percent return and proceeds of $71.2 million in the transaction.

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