Betting Markets Now Favor Anthropic, Not SpaceX, For Biggest 2026 IPO

Money is moving fast on a bet that didn't even look close a month ago.

As of Wednesday, August 26, a Polymarket proposition titled "Largest IPO by market cap in 2026?" shows Anthropic at 58% odds to post the biggest public offering of the year, with SpaceX at 44%, according to Forbes. This represents a sharp reversal. Forbes reports SpaceX's odds were as high as 90% just two weeks earlier. CoinGape's data from August 14 shows SpaceX was priced at 71% and Anthropic at roughly 27% then, after starting the month at 94% for SpaceX. Traders have put more than $5.6 million into the market, according to Forbes, split almost evenly between the two bets.

The shift didn't happen in a vacuum. Anthropic confidentially filed its IPO paperwork with the SEC last month, and Bloomberg reported the company is now scheduling investor meetings ahead of a possible roadshow, according to CNBC's reporting cited by Breitbart. Goldman Sachs, Morgan Stanley and JPMorgan Chase are running the process. Bloomberg first reported that a debut could come as soon as October, though Breitbart notes the timing "remains subject to change."

The Numbers Driving The Bet

Anthropic's revenue is driving the shift. Bloomberg reported the company's annualized revenue is on pace to top $65 billion in 2026, up from a $47 billion pace in May, according to both Yahoo Finance and Hindustan Times. That kind of growth rate is pulling institutional money toward a much richer valuation.

Anthropic is telling prospective investors it sees more than $30 trillion in potential total addressable revenue, the Wall Street Journal reported Tuesday, according to Forbes. That figure tops the $28.5 trillion market estimate SpaceX gave investors ahead of its own offering. Anthropic is reportedly targeting a valuation as high as $2 trillion and could raise up to $100 billion, per Forbes. Private-market data from Yahoo Finance puts Anthropic's current valuation around $1 trillion, ahead of rival OpenAI's roughly $894 billion.

Where SpaceX Actually Stands

None of this means SpaceX had a bad IPO. It priced at $135 a share on June 11, according to Yahoo Finance, and opened around $150 on its June 12 Nasdaq debut. It closed its first day at $160.95, a 19.2% pop that pushed its market cap to about $2.1 trillion, one of the largest single-day valuations in market history.

Shares later climbed to around $225 before sliding hard, bottoming near $104 to $106 amid investor concerns over lockup expirations and capital spending plans, according to Yahoo Finance and Forbes. As of the close on August 26, SpaceX shares sat at $139.63, up 1.22% on the day, per Yahoo Finance's AlphaSpace data. Yahoo Finance had separately reported the stock rallying to around $146 a share for a market cap of about $1.93 trillion earlier in the week. Sevens Report Research founder Tom Essaye told Yahoo Finance's Opening Bid that "betting against Elon Musk has been a fool's errand time and time again," while also warning investors to "buckle up for some interim volatility."

SpaceX is also still spending big on its core business. Finanznachrichten.de reported the company unveiled plans for a $100 billion "Starbase Louisiana" facility in Vermilion Parish, with construction expected to begin in 2027 and first launch targeted for 2029. SpaceX says the site will eventually support thousands of Starship launches a year and could create roughly 3,000 direct jobs.

What This Bet Actually Measures

Under the Polymarket rules described by CoinGape, the winner is whichever company completes an IPO in 2026 and finishes its first trading day with the higher market capitalization, shares outstanding times closing price. Anthropic has not filed a public S-1, has not set a share price, and has not confirmed a listing date. An Anthropic spokesperson declined to comment on IPO plans, according to Breitbart.

This is a prediction market pricing an event that hasn't happened, based on a confidential SEC filing, investor-meeting scheduling reported secondhand, and a revenue trajectory that could shift before any roadshow launches. Traders are effectively betting that a company that hasn't priced a single share will beat a company that already posted one of the largest debuts in market history.

Meanwhile OpenAI, Anthropic's chief rival and also a confidential SEC filer since June, isn't registering as a serious contender in the Polymarket data at all. The Epoch Times reported that OpenAI has lost a string of senior executives this year, including chief revenue officer Denise Dresser, product chief Fidji Simo, and longtime executive Brad Lightcap. Kevin McCormick, founder of AI startup SignAudit.AI, called the exodus "a huge red flag" ahead of an IPO in a post cited by Epoch Times. Paul Meeks, head of technology research at Freedom Capital Markets, told Epoch Times that OpenAI "looks like they're pushing their IPO until" next year. OpenAI has not confirmed a delay.

The open question is simple: does Anthropic actually file publicly and price shares before year's end, and at what valuation. Nothing is locked until an S-1 hits the SEC's public docket and a bank sets a share price. Until then, the 58% is a bet on a rumor, not a result.