'Shark Tank' star Kevin O'Leary slams Bitcoin as niche and poorly regulated: 'a giant nothingburger'

• "Shark Tank" investor Kevin O'Leary criticized Bitcoin as niche, illiquid, and poorly regulated.
• "Bitcoin is still a nothingburger, a giant nothingburger," he said on his YouTube channel.
• O'Leary emphasized the potential for a global digital currency approved by regulators.
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"Shark Tank" star Kevin O'Leary dismissed Bitcoin as too niche, illiquid, and badly regulated to justify a substantial investment in an interview this week.

"I look at the asset value of Bitcoin versus the asset value of all things traded and Bitcoin is still a nothingburger, a giant nothingburger," he told investor Anthony Pompliano in a video on his YouTube channel.

"You don't have every institution willing to play ball with it," the O'Leary Funds and O'Leary Ventures chairman continued.

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O'Leary - whose nickname is "Mr. Wonderful" - added that it's a headache to buy a large sum of Bitcoin and a pain to navigate the regulatory minefield around cryptocurrencies.

"If I want to buy a million dollars' worth of Bitcoin right now, I've gotta do a fair amount of work to pull that off," he said. "I can't get consistency with any single regulator on endorsing bitcoin for me to actually do a significant transaction."

However, O'Leary underscored the rich potential for a digital currency that is widely approved by regulators and can be used to buy assets around the world.

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"Then you would have something of tremendous value," he said. "That is a vision that's really attractive versus this tiny little thing."

O'Leary voiced similar criticisms in a CNBC interview last month. The size of the Bitcoin market makes it "completely irrelevant to the institutional client," he said.

The veteran investor also highlighted a regulatory crackdown as a major risk for crypto fans. "Grown men are going to weep when that happens," he said. "It will be brutal."

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O'Leary proposed a solution to his concerns on "The Pomp Podcast" last month: a cryptocurrency ETF approved by regulators.

"Give me the top seven cryptocurrencies, put them into an ETF wrapper, and let me invest in it with liquidity, so that if I want to buy a million dollars of it in the morning and sell a million dollars in the afternoon, I can do that in an ETF format," he said.