SpaceX IPO vs Anthropic IPO: Which Is Bigger and Why?

Which is bigger, the SpaceX IPO or the Anthropic IPO?

By money raised in the public offering, the SpaceX IPO is bigger, and on the numbers filed so far Anthropic cannot overtake it. SpaceX raised $75 billion when it priced on 11 June 2026 and $85.7 billion after its underwriters bought extra shares; Anthropic's planned offering tops out at about $64.35 billion, or about $74 billion with its own extra shares ^[1][4][5].

The answer depends on what you measure. There are three common ways to compare the two deals:

• Deal size (money raised): SpaceX is ahead, whatever price Anthropic sets within its range ^[1][4].
• Valuation (what the whole company is worth at the offer price): SpaceX is also ahead, at nearly $1.75 trillion against up to $1.404 trillion for Anthropic ^[6][8].
• Total new money around the listing: here Anthropic comes close, because it adds a $26 billion private placement on top of the IPO ^[1].

SpaceX's offering is already finished, so its numbers are results. Anthropic's are still plans. The company is expected to set its final price on Wednesday 18 November and start trading on Thursday 19 November ^[3]. Until then, every Anthropic figure below is a range, not a fact ^[7].

For the Anthropic offer itself, including the timetable and how retail buyers can take part, see the Pouyam guide Anthropic IPO: Date, Price Range and How to Buy ANT Shares.

How much did SpaceX raise compared with Anthropic's target?

SpaceX raised $75 billion at a fixed price of $135 per share, and the total grew to $85.7 billion after underwriters exercised their option to buy an additional 83.3 million shares ^[4]. Anthropic's offer of 825,000,000 shares at $70 to $78 works out to $57.75 billion to $64.35 billion ^[1][8].

The Anthropic numbers come straight from its amended registration statement, filed with the US Securities and Exchange Commission on 10 November 2026 ^[1]. Of the 825,000,000 Class A shares, 801,351,354 are new shares sold by Anthropic and 23,648,646 are sold by existing shareholders, who keep that money ^[1][2]. Underwriters led by Goldman Sachs and Morgan Stanley also get a 30-day option to buy up to 123,750,000 more shares from the company ^[1][2].

That extra option is often called the greenshoe. Underwriters normally use it when a stock trades well after its debut ^[4]. For a like-for-like comparison:

• Base deal: SpaceX $75 billion against Anthropic $57.75 billion to $64.35 billion ^[1][4][8].
• With the greenshoe: SpaceX $85.7 billion against Anthropic about $66.4 billion to $74.0 billion, if all 948,750,000 shares are sold (a calculation from the filing) ^[1][4].

Reuters, which reported the upper figure as up to $64.4 billion, noted that SpaceX's $75 billion was more than double the money raised in Saudi Aramco's 2019 listing, the previous record ^[5][7].

How do the SpaceX and Anthropic valuations compare?

At the offer price, SpaceX was valued at nearly $1.75 trillion, according to Reuters, while Anthropic would be worth up to $1.404 trillion on a fully diluted basis if it prices at $78 ^[6][8]. After its first day of trading, SpaceX closed at $160.95, which valued it at about $2.1 trillion ^[5].

Anthropic's valuation has moved a lot this year. TechCrunch reported that the top of the range is well above the $965 billion valuation from a private fundraise in May, but below the roughly $2 trillion the company was reportedly targeting a couple of months earlier ^[8]. Reuters said investors had once discussed a valuation of as much as $2 trillion, but expectations have since fallen amid Anthropic's hefty infrastructure commitments and volatility in AI-related stocks ^[5].

Valuation and deal size are different things. A company can be worth more but sell a smaller slice of itself. Reuters estimated that only about 6% of Anthropic's outstanding shares are being offered in the IPO ^[6]. Based on the reported figures, SpaceX's $75 billion base deal was a little over 4% of its IPO valuation, a calculation from the Reuters numbers rather than a company disclosure ^[6].

These figures say nothing about whether either share is cheap or expensive. They describe the size of each listing, not its future returns.

Why is the SpaceX IPO bigger than Anthropic's?

The SpaceX IPO is bigger because it was sold at a higher price per share ($135 against $70 to $78) and at a higher valuation, and because underwriters later added extra shares after the stock rose ^[4][5][6][8].

Several points explain the gap:

1. Higher starting valuation. SpaceX listed at nearly $1.75 trillion, while Anthropic's range implies up to $1.404 trillion ^[6][8].
2. A fixed price. SpaceX broke with Wall Street custom by setting its price before the investor roadshow, instead of marketing a range first ^[5]. Anthropic is following the usual path of a range and a roadshow, which started on 10 November ^[2].
3. The greenshoe. SpaceX shares rose 19% on their first day, so underwriters used their option and added about $10.7 billion ^[4]. Anthropic's option will only count if demand is strong after 19 November ^[1].
4. A separate private sale. Anthropic is raising part of its new money outside the IPO, through a $26 billion private placement with large technology companies, so that money is not counted in the public deal size ^[1][5].

Market conditions also changed between June and November. TechCrunch described Anthropic as pressing ahead despite shakier markets and a broader pullback from AI investing ^[8].

Does Anthropic's $26 billion private placement change the answer?

It changes the picture for total new money but not the IPO ranking: the $26 billion of Class N shares sold to Google, NVIDIA, AMD, Broadcom, Micron, Microsoft and TSMC is a private sale at the IPO price, not part of the public offering ^[1].

According to the filing, these companies will buy the shares at a price equal to the IPO price, just after the offering is completed ^[1]. At the $74 midpoint, Google and NVIDIA would each buy about $10.0 billion ^[1]. The shares are not registered in the offering and are restricted securities, so the buyers cannot simply sell them on the market right away ^[1].

Anthropic estimates its net proceeds from the IPO and the private placement together at about $84.6 billion at the midpoint, or about $93.7 billion if the underwriters' option is fully used ^[1]. Net means after underwriting fees, which apply only to the public shares ^[1].

So if you add the private placement, Anthropic's total fundraising around its listing could be close to, or above, the $85.7 billion SpaceX raised in its offering ^[1][4]. Reuters, however, gives Anthropic's offering as up to $64.4 billion and the separate $26 billion placement on its own, so its offering sits below SpaceX's record $75 billion ^[5].

How are the two IPOs structured differently?

The two deals share some new features, such as a large retail slice and fast index entry, but differ in pricing method, ownership and control ^[5][6].

What is similar:

• Retail allocation. SpaceX set aside about a fifth of its offering for individual investors, more than double the usual share, and Anthropic is doing the same, according to Reuters ^[6].
• Fast index inclusion. After index providers such as Nasdaq rewrote their inclusion rules, a large pool of passive money was set to buy SpaceX shares in the first 15 days of its listing. Anthropic is expected to be added to at least six big indexes, including the Nasdaq 100, within 5 to 15 days of listing ^[6].
• Same exchange and lead banks. Both chose Nasdaq, and Goldman Sachs and Morgan Stanley appear among the underwriters in both deals ^[1][4]; Nasdaq is the exchange for both ^[1][5].

What is different:

• Pricing. SpaceX fixed its price in advance; Anthropic will set its price after the roadshow, within or possibly outside the $70 to $78 range ^[1][5].
• Corporate form. Anthropic is a Delaware public benefit corporation with several share classes and says it will be a controlled company under Nasdaq rules ^[1].
• Selling shareholders. Part of Anthropic's offer, 23,648,646 shares, comes from existing holders, so that money does not go to the company ^[1][2].

For details of who controls Anthropic and how its share classes work, see the Pouyam guide Anthropic IPO Filing: Revenue, Losses and Who Controls It.

What did SpaceX shares do after the IPO?

SpaceX shares jumped 19% on their first trading day to close at about $161, then drifted lower but stayed above the $135 offer price; they closed at $142.07 on 9 November 2026 ^[4][5].

Reuters reported that SpaceX opened at $150 and stayed above the IPO price for its first 15 days of trading, with index funds and retail investors taking nearly half the shares sold. After that, the shares slipped as investors prepared for the end of lock-up periods, when employees and early backers are allowed to sell ^[6].

Analysts are studying this pattern for clues about Anthropic. One London index analyst described Anthropic as a mirror image of the SpaceX IPO, with the same index-related drivers over the first 15 days of trading ^[6]. Index analytics firm Intropic estimated that passive index funds could account for about 28% of the Anthropic shares offered, or roughly $19 billion ^[6].

A similar start is not guaranteed. What happened to one stock after its debut does not predict what will happen to another, and both companies carry their own risks, which are set out in their filings. For SpaceX's share history and risks, see the Pouyam guide SpaceX Stock Price (SPCX): The IPO, Price History and Key Risks.

What happens next with the Anthropic IPO?

Anthropic is expected to set its final offer price on Wednesday 18 November and to begin trading on Nasdaq under the symbol ANT on Thursday 19 November 2026; only then will its exact size and valuation be known ^[3].

Three things will decide how the final comparison with SpaceX looks:

1. The final price. Each $1 per share changes the base deal by $825 million, so the gap with SpaceX narrows or widens with the pricing ^[1].
2. The greenshoe. If the shares trade well, underwriters can buy up to 123,750,000 more within 30 days, adding up to about $9.7 billion at $78 ^[1][2].
3. First-day trading. The closing price on 19 November will set the market value that headlines compare with SpaceX's $2.1 trillion first-day valuation ^[5].

Whatever the result, the SpaceX deal remains the record for money raised in a single IPO unless a future offering, such as a possible OpenAI listing, overtakes it; Reuters reports that OpenAI's chief executive said it will not go public in 2026 and its president said it expects to be ready in 2027 ^[5].

This guide compares the size of two listings. It is not a recommendation to buy or sell any shares. Anyone considering an IPO should read the prospectus and, where needed, speak to a licensed adviser.