Bitcoin slid on Tuesday after a volatility attack underscored doubts about the durability of the token’s wild rally.
The cryptocurrency fell as much as 11% to below $50,000.
At one point on Monday, the digital currency plunged 17% before paring the worst of the slide though it is still up some 400% in the past year.
Treasury Secretary Janet Yellen and Microsoft Corp. co-founder Bill Gates were the latest to weigh into a debate over the digital coin.
Gates cautioned about how investors can be swept up in manias, while Yellen said Bitcoin is an “extremely inefficient way of conducting transactions.”
Gates and Yellen muscled in on a Bitcoin discussion that of late had been dominated by Tesla Inc. Chief Executive Officer Elon Musk.
In recent tweets, Musk said Bitcoin prices “seem high,” having earlier called it a “less dumb” version of cash.
Tesla this month disclosed a $1.5 billion investment in Bitcoin, while MicroStrategy Inc. boosted a sale of convertible bonds to $900 million to buy even more of the token.
Bitcoin faithful argue the digital currency emerging as a hedge for risks such as faster inflation and set to win more attention from corporate treasurers and institutional investors.
Others see speculators playing a bigger role and some echoes of the digital coin’s 2017 boom and bust.
Bitcoin was trading at about $49,720 as of 1:17 p.m. in Hong Kong on Tuesday.