When Tesla revealed on Monday that it had taken a $1.5 billion stake in Bitcoin, the news caused the price of the digital currency to soar. By Tuesday afternoon, Bitcoin had jumped nearly 20%, to a record $48,000.
The surge is partly the result of hype generated by Tesla’s celebrity CEO, Elon Musk. But some investors also view the company’s embrace of Bitcoin as a sign that other big companies will follow suit. According to RBC research, even Apple—the world’s most valuable company—may get into the Bitcoin game. (Apple has not responded to Fortune‘s requests for comment on the matter.)
For all the attention it got, Tesla is hardly the first publicly traded company to buy Bitcoin, as the chart below shows—nor does it own the most. The latter distinction belongs to Microstrategy, a once-obscure software firm that bet big on Bitcoin in 2020.
The figures for Tesla and for Mass Mutual, the fourth-biggest public- company Bitcoin owner, are estimates, because both companies have only disclosed how much they spent—$1.5 billion and $100 million respectively—not how many Bitcoins they bought. The estimates are based on the price of Bitcoin around the time the companies made the purchases.
The chart also highlights a significant point: Four of the top six companies listed—Microstrategy, Tesla, Mass Mutual and Square—are not primarily cryptocurrency companies, having made their name in other arenas.
It should be noted that the chart excludes what BitcoinTreasuries.org (the source of most of the data above) describes as “ETF-like” companies, which package Bitcoin as common investments like shares for their customers. The biggest of that group, Grayscale, towers over the industry with over 600,000 Bitcoins under its control—more than 3% of all Bitcoins in circulation, a stash whose value is almost $30 billion at current prices.
While the Bitcoin stashes of Tesla and Square are valuable, those companies’ holdings are still smaller than those of some individual “whales”—crypto parlance for people who hold a lot of Bitcoin. Fortune reported in 2018 that there are dozens of such whales, who held between 12,000 and 80,000 Bitcoins each; those numbers may have grown since then.
As for the decision of Tesla, Square and other public companies to move into Bitcoin, it appears to have paid off so far, given the asset’s current all-time high price. The value of their holdings has appreciated dramatically, with a return far greater than that of bonds or money market funds—which is where most companies park their spare cash. While they would face tax bills if they sold Bitcoin to capture gains, their after-tax returns would likely far exceed what they’d have gotten from those safer-haven assets.
But the move is highly risky as well. Not only is Bitcoin prone to spectacular collapses—its price fell over 80% when the 2017 crypto bubble popped—but it’s also subject to quirky accounting rules. As Fortune‘s Shawn Tully recently noted, companies can’t claim Bitcoin price appreciation on their balance sheets. But if the price falls, they are forced to report an impairment, which knocks down a firm’s overall value.
In short, it looks like Tesla made a shrewd move for now at least. But other companies are likely to take a wait-and-see approach before following the handful of publicly traded firms that have put Bitcoin on their balance sheet.