These experts are often crypto billionaires who have a thorough understanding of virtual digital assets (VDAs) and their underlying blockchain technology. However, not all of these individuals share the same outlook toward cryptocurrencies. While some advocate the use of VDAs, quite a few detest their existence. Here's a round of such millionaires who strongly opposed the digital asset class but later changed their minds.

Warren Buffett | The Berkshire Hathaway boss has never held back his opinion on virtual digital assets. He has been known to call cryptocurrencies worthless and "rat poison squared." When asked about Bitcoin at Berkshire's shareholder meet, the Oracle of Omaha famously said, "If you owned all of the Bitcoin in the world and offered it to me for USD 25, I wouldn't take it because what would I do with it?" However, a few years after his statements, it was revealed that Berkshire Hathaway pumped USD 1 billion into the crypto-friendly Brazilian Nubank. More surprising is that Hathaway sold USD 1.3 billion and USD 1.8 billion worth of stocks from Mastercard and Visa, respectively, before investing in Nubank. This could indicate that the investment giant is slowly warming up to the digital asset class.

Howard Marks | Howard Marks has been lauded for having foreseen the dot com bubble and the impending financial crisis in the late 2000s. The co-chairman and co-founder of Oaktree Capital also wrote a memo in 2017 wherein he bashed digital currencies. "In my view, digital currencies are nothing but an unfounded fad (or perhaps even a pyramid scheme), based on a willingness to ascribe value to something that has little or none beyond what people will pay for it," wrote Marks at the time. But in March 2021, Marks reconsidered his "dismissive" stance on bitcoin. In an interview with the Korea Economic Daily, he said that his statement in the memo was "a knee-jerk reaction without information." He also mentioned that he was glad his son owned Bitcoin.

Mark Cuban | In September 2019, the billionaire owner of the Dallas Mavericks said that he saw no foreseeable future where Bitcoin became a reliable currency. "No chance," said Cuban. "Not because it can't work technically, although there are challenges, it could, but rather because it's too difficult to use, too easy to hack, way too easy to lose, too hard to understand, too hard to assess a value," he elaborated in his e-mail. However, at this year's North American Bitcoin Conference, Cuban admitted to having minted his first NFT in 2021. Since then, Cuban has made investments in Cryptocurrencies like Dogecoin and Ether, Web3, several blockchain companies, and even Yuga Labs – the creator of the infamous Bored Apes Yacht Club NFT collection. That's quite a U-turn from his initial perspective on the digital asset class.

Carl Icahn | The billionaire investor and Chairman of Icahn Enterprises told CNBC in February 2018 that Bitcoin and the other cryptocurrencies were "ridiculous." Then, about three years later, in May 2021, the former crypto sceptic told Bloomberg that he was contemplating a massive USD 1.5 billion investment in the crypto industry. By October 2021, Icahn even believed that Bitcoin might be the best hedge against inflation.

Øystein Stray Spetalen | This Norwegian billionaire investor is one of the lesser-known names in the crypto industry. At a DNB Invest conference in March 2021, Spetalen verbally thrashed Bitcoin and called it a "nonsense currency." "Bitcoin today consumes as much energy as all of Norway. It is extremely environmentally hostile. The authorities and the EU should ban it immediately. Then you'd cut CO2 emissions considerably," he was quoted as saying. "It's just nonsense. We're doing well with the payment systems that are in place today," he had added. However, within a month, Spetalen completely reversed his outlook and revealed that he was now the owner of MiraiEx - the largest Bitcoin exchange in Norway. In an interview with the Norwegian local publication Finansavisen, he conceded that he had reconsidered after one of his fellow billionaires entered Bitcoin. The incident humorously became known as "billionaire FOMO."