Last month, Tesla updated its investment policy so that it could diversify cash holdings that aren’t required for operating liquidity. Those holdings, which are bulging after selling billions of dollars in new stock, jumped to almost $20 billion at the end of 2020, up from around $6 billion at the end of the previous year.

“We may invest a portion of such cash in certain alternative reserve assets including digital assets, gold bullion, gold exchange-traded funds and other assets as specified in the future,” the company said in its filing. “We believe our bitcoin holdings are highly liquid. However, digital assets may be subject to volatile market prices, which may be unfavorable at the time when we want or need to liquidate them.”

Like bitcoin, Tesla has been the subject of intense speculation by retail traders. The car company’s market capitalization is now double that of automakers GM, Ford, Toyota, and BMW put together. Bitcoin, which can’t be valued in the way that a stock or a currency can be, was recently given the highest “bubble score” by JPMorgan’s analysts.

Bitcoin has had multiple booms and busts since it was created in 2009, and prices in the crypto asset have recently surged along with a broader rally in tech stocks. PayPal started a service in November that allows users to buy and sell bitcoin, and Square, whose founder has suggested bitcoin could be the internet’s native currency, said it bought about $50 million worth of the crypto.

By some measures, bitcoin hasn’t caught on widely as a means of payment. Stripe, the payment processor and fintech darling, discontinued support for it in 2018, citing “fewer and fewer use cases for which accepting or paying with Bitcoin makes sense.” And companies that accept bitcoin for transactions don’t necessary hold the crypto asset, and may instead have the funds switched into fiat currencies immediately. However bitcoin has caught on as a means of speculation. Some proponents say it could be used to store value, like a digital gold. Hedge fund manager Paul Tudor Jones (also no stranger to speculation) said in May that he had put a slice of his assets in bitcoin.

If bitcoin and Tesla one day come to represent the ongoing trading mania, the question is whether they will be like Amazon and Google, which went on to become titans of the modern economy after the dot-com bubble—or will be more like Yahoo and AOL, which are a shadow of their pre-boom selves.

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