Anthropic plans to raise up to $64.4 billion in its stock market debut, a headline figure that would still fall short of the $75 billion SpaceX collected in its completed listing, according to Reuters. The comparison of three mega-IPOs (initial public offerings, the first sale of a company's shares to outside investors) places Anthropic second by size, with OpenAI yet to declare either a figure or a date.

Reuters weighed SpaceX's listing against the debuts planned by AI makers Anthropic and OpenAI. Anthropic is likely to sell shares before 2026 ends, according to Reuters expectations reported by The Next Web. OpenAI will wait longer: chief executive Sam Altman said in September the company would not list this year, and OpenAI expects to be in position for a public sale in 2027.

Why are rival AI makers converging on public markets at once?

The three debuts come from competitors racing to build the same technology. Even the rocket maker is now partly an AI company. CNBC reports SpaceX merged with Elon Musk's AI company, xAI, earlier in 2026, so buyers of SpaceX stock buy into AI alongside rocket launches. SpaceX's own filing names OpenAI, Anthropic and Google as key AI competitors, putting the maker of ChatGPT and the maker of Claude on opposite sides of the same contest.

Investors who never buy a share already carry exposure. SoftBank, an OpenAI investor, saw its shares fall as much as 13% in June after a report that OpenAI's listing could slip, according to The Next Web. For ordinary investors, the question is not only whether these debuts set records, but whether the prices behind them hold once trading begins and early excitement fades.

What does Anthropic's $64.4 billion actually represent?

The figure is a ceiling, not an expectation. Anthropic is seeking up to $64.4 billion at a valuation of roughly $1.4 trillion, according to Reuters, with shares priced between $70 and $78, CNBC reports. Any price below $78 means Anthropic raises less than the headline. Even at $78, it would collect less than SpaceX, which raised $75 billion according to Reuters and $85.7 billion according to CNBC.

Anthropic has already scaled back its ambitions. The company earlier aimed for a $2 trillion valuation, according to Reuters and CNBC, well above the roughly $1.4 trillion target now. One Anthropic investor told CNBC a valuation above the current target would be a "stretch." The likely result is a sum at or below the headline, leaving Anthropic further from the record.

Part of the raise comes from Anthropic's own suppliers. AMD, Broadcom, Google, Micron, Microsoft, Nvidia and TSMC — all of which do business with Anthropic — are buying $26 billion of stock in a private placement (a share sale to selected investors rather than the open market) held alongside the offering, according to CNBC. That support is real money, but it comes from partners whose sales depend on Anthropic's spending, so it reveals less about outside demand than the size suggests. The verdict arrives only when trading begins and buyers without a business stake judge whether $78 a share was worth paying.

Where does OpenAI stand without a price or a date?

Private investors already value OpenAI at $1.25 trillion, according to Reuters, placing its planned listing among the largest debuts ever. How much stock it will sell, and when, remains unknown. The private valuation has climbed fast: investors valued OpenAI at $852 billion in late March, according to CNBC, while Altman is aiming for a $1 trillion listing valuation, Bloomberg reporting carried by The Next Web shows. That target sits below the last private price, so the debut may not clear the private peak.

OpenAI has little reason to hurry. It has closed $11 billion in new private money, and it has stated its own case for waiting. "We have not decided on timing yet; it may be a while because there are things we want to do that are likely easier as a private company," OpenAI said in a statement, as reported by CNBC. Public buyers would also judge a trillion-dollar price without some basic facts: most of OpenAI's sales come from businesses, The Next Web reports, but the company has given no figure for that share.

What does SpaceX's completed sale tell investors?

SpaceX raised $75 billion when it went public, according to Reuters — a result rather than a plan. Buyers in the offering paid $135 a share, and the stock closed its first trading day at $160.95. That enthusiasm has faded without turning into a loss: at the close on November 9, the shares traded at $142.07, below the first-day close but above the offering price. First-day buyers remain ahead, though most of the initial gain is gone.

OpenAI announced its confidential filing to go public on June 8, 2026, according to CNBC, in the same month SpaceX listed. If investors keep treating SpaceX well, Anthropic and OpenAI could speed up their own listings — a response that remains unsettled. SpaceX shares, above the offering price but below the first-day close, are the standard investors will apply when the AI makers finally name their prices.