Programmer has two guesses left to access £175m bitcoin wallet

Stefan Thomas has just two chances left to get his hands on his $240m (£175m) fortune.

Thomas is a San Francisco-based computer programmer, and a decade ago he was given 7,002 bitcoins as a reward for making a video explaining how the cryptocurrency works.

At the time he was paid, they were worth $2-$6 each. He stashed them away in his “digital wallet” and forgot about them.

Now each bitcoin is worth $34,000, and the contents of his wallet are valued at $240m. But Thomas has forgotten the password that will unlock his fortune.

German-born Thomas has already entered the wrong password eight times, and if he guesses wrong two more times his hard drive, which contains his private keys to the bitcoin, will be encrypted – and he’ll never see the money.

The price of bitcoin hit more than $40,000 last week, having doubled in less than a month. It has since fallen back but it is still up by more than 700% since the pandemic was first declared in March last year, rising from about $5,000.

Thomas said he has tried his eight most frequently used passwords to access his IronKey hard drive, but all turned out to be wrong. The device auto-encrypts all contents after the 10th inaccurate guess.

“I would just lay in bed and think about it,” Thomas told the New York Times. “Then I would go to the computer with some new strategy, and it wouldn’t work, and I would be desperate again.”

Thomas said the experience has understandably put him off cryptocurrencies. “This whole idea of being your own bank – let me put it this way, do you make your own shoes?” he said. “The reason we have banks is that we don’t want to deal with all those things that banks do.”

Following the publicity of Thomas’s plight, Alex Stamos, an internet security expert at Stanford Internet Observatory, said he could crack the password within six months if Thomas gave him a 10% cut of the digital fortune.

“Um, for $220m in locked-up bitcoin, you don’t make 10 password guesses but take it to professionals to buy 20 IronKeys and spend six months finding a side-channel or uncapping,” he said on Twitter. “I’ll make it happen for 10%. Call me.”

Cryptocurrency data firm Chainalysis said it estimated that about 20% of the existing 18.5m bitcoins appears to be lost or stranded in inaccessible wallets.

In 2013, Welsh IT worker James Howells accidentally threw out a hard drive containing the keys to 7,500 bitcoins. At the time, the lost bitcoins were worth about £4m. Now, they would be worth more than $250m.