Shares of Elon Musk's SpaceX soared more than 14% on Tuesday, lifting its value higher than Amazon and briefly Microsoft just days after its debut.
Shares in the rocket and AI company were selling for $220 (£164), more than 62% above the $135 (£101) Initial Public Offering (IPO) price, giving the company a market capitalisation of about $2.85trn (£2.12trn).
SpaceX's share market rally saw the company top Amazon's valuation of $2.64trn (£1.97trn) and briefly beat Microsoft's of $2.92trn (£2.18trn), as it joined the ranks of the five most valued companies.
Amazon's revenue grew to $717bn (£543bn) last year, while SpaceX reported sales of $18.67bn (£13.91bn) and a net loss of $4.94bn (£3.68bn) after merging with money-losing xAI, in sharp contrast to many of Wall Street's biggest technology companies that have returned strong profits.
Analysts and portfolio managers said investors should brace for volatility due to SpaceX's relatively small float and high valuation, particularly early on in the company's life as a public company.
"We can say with certainty that this valuation makes absolutely no sense today," said Ipek Ozkardeskaya, senior market analyst at Swissquote Bank.
"People are buying SpaceX in the expectation that others will buy too and push the price higher - that's speculation."
SpaceX options have also began trading, offering investors another avenue to bet on the future of the newly listed shares.
"Today the SPCX options launch, offering standard monthly expiration and strikes ranging from $25 to $380," said Brent Kochuba, founder of option analytics platform SpotGamma.
"If call demand is heavy, dealers might be forced to buy SPCX into this low-liquidity situation.
"Starting next week we may see index demand increase, with more shares not slated to be made available for one to two months."
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SpaceX's rally could continue with the company set for fast-track inclusion in the Nasdaq 100, which will make it a major holding for passive funds and ETFs that track the index.
FTSE Russell and MSCI are also set to add the stock to their indexes, from 26 June and 29 June, respectively.
"While index inclusion alone is typically insufficient to drive sustained repricing, we see the combination of passive flows, momentum, and limited float driving upside beyond historical index-addition moves," brokerage Zephirin Group said.
SpaceX said on Monday its underwriters had exercised the "greenshoe" option to purchase additional shares, increasing the total proceeds from its initial public offering to $85.7bn (£63.86) from $75bn (£55.88bn).
Earlier in the day, SpaceX also said it would acquire software company Anysphere for $60bn.
(c) Sky News 2026: Shares of Elon Musk's SpaceX soar past Amazon
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