But fans of the digital coin have not taken the criticism sitting down, and some are taking aim at the J.P. Morgan CEO. Fans pointed out that Dimon's firm had in fact gotten involved with bitcoin and blockchain (a digital ledger commonly used for bitcoin transactions) in the past. The banking giant at one point tried to file a patent for a bitcoin-style payment system—an applicaiton that was reportedly rejected.
In response to Dimon's comments, J.P. Morgan's former global trading macro head tweeted: "Jamie, you're a great boss and the GOAT bank CEO. You're not a trader or tech entrepreneur. Please, STFU about trading BTC."
J.P. Morgan's blockchain lead Amber Baldet meanwhile responded with a virtual shrug to the news:
Bitcoin backer and creator of McAfee Associates John McAfee also weighed in , telling CNBC that Bitcoin was no fraud.
"You called bitcoin a fraud," McAfee said Thursday. "I'm a bitcoin miner. We create bitcoins. It costs over $1,000 per coin to create a bitcoin. What does it cost to create a U.S. dollar? Which one is the fraud? Because it costs whatever the paper costs, but it costs me and other miners over $1,000 per coin. It's called proof of work."
Barry Silbert, the CEO of Digital Currency Group meanwhile shot back:
A former stock trader who was convicted of insider trading—Michael Kimelman—meanwhile pointed out the irony of J.P. Morgan's head calling bitcoin a "fraud."
Finally, one Twitter user characterized the fury directed toward Dimon as something of a digital mob:
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