Anthropic IPO odds on Polymarket have settled into a clear year-end lean. As of October 1, 2026, the odds of a completed public sale by December 31 stand at 82%, with November leading at roughly 60% to 61% and October near 3%. Traders are treating a 2026 listing as likely, while treating this new current month as almost closed.
The month contract tells the same story in finer detail. A live Polymarket tracker updated on October 1 put November 2026 at 58.6%, December 2026 at 17.4%, January 2027 at 5.1%, and October 2026 at 2.5%. Total volume stood near $300,800, with about $8,600 traded over the prior day and about $44,400 in liquidity. Prices are moving, but they are not thrashing.
Moonberg’s October snapshot lined up with that year-end read, putting a completed listing by the end of 2026 near 83% and a confirmed deal near 82%. The same snapshot put a listing by the end of November near 69%. These contracts pay on the first day public company shares are listed and open for regular trading, counted in Eastern Time, not on a filing, a leak, or a roadshow start.
What are the current Anthropic IPO odds by month?
November is carrying the Anthropic IPO timing trade. December holds the second-highestodds, and every later month sits in the single digits. October’s drop toward 3% means traders have mostly written off a debut before November. A mid-October roadshow can still happen.
Kalshi has been pricing a narrower question. Kalshi’s odds of an announcement before November rose from 4.7% on September 28 to 16% on September 30. An announcement is obviously not a listing, and traders should always read market rules before entering markets, too. Be clear on settlement rules. A company can file, talk to accounts, and still miss the month traders have circled. Again, read the market rules.
Earlier September reads sat a step lower. As of September 28, Polymarket showed a 54% to 58.5% chance of an IPO by November 30, with December 31 nearer 74% to 79%. The October 1 reading at 82% extends that climb rather than marking a one-day spike.
Why did Anthropic IPO timing slip from October to November?
Anthropic opened the door itself on June 1, 2026. The company said it had confidentially submitted a draft Form S-1 to the SEC for a proposed IPO of common stock, and that any deal would depend on market conditions and other factors. Share count and price were not set.
Reporting through September pushed the working calendar later. CryptoBriefing said the original target was an October launch, then shifted to November so the deal could include third-quarter figures ahead of the midterms. Goldman Sachs, JPMorgan, Morgan Stanley, and Citi were described as lead underwriters, with talk of a raise of up to $100 billion. A public prospectus that some desks expected in September did not land on that earlier schedule.
Reuters equity correspondent Echo Wang, speaking on ABC News (Australia), said the public filing expected in September did not arrive, and that the IPO could drag until after the midterms. She also flagged a tight window after that, with Thanksgiving and then year-end holidays leaving little time for a mega IPO deal.
A separate timeline briefing has been tracking the same slip, including reports that the deal moved into November and that Nasdaq was the chosen venue. None of that is a company release, but rather analyst coverage of the markets. Anthropic has not posted a listing date, an offering size, or a price range.
How does the leaked Anthropic prospectus change the Anthropic IPO valuation case?
IFR reported that a leaked draft prospectus, prepared ahead of a Nasdaq listing intended for November, showed supplier liabilities of at least $518 billion over the coming decade. The commitments run to Alphabet, Amazon, Microsoft, Broadcom, SpaceX, and AMD, and about 80% were described as non-cancellable or payable regardless of use. Bankers were targeting about $100 billion of proceeds at a $2 trillion valuation.
InvestmentNews, citing the prospectus, said revenue rose roughly twelvefold last year to nearly $4.6 billion, while operating losses topped $8 billion. Google was owed at least $111.1 billion, Amazon about $110 billion, and Microsoft about $31.4 billion. The filing language was blunt: if actual spend falls short, Anthropic must pay Google the difference. Nearly 25% of revenue came from two customers, so the growth story and the fixed bill are tied together.
The prospectus ran about 261 pages, with roughly 80 pages on risk and 48 on the business. It warned that the models could blackmail or resist shutdown, and pointed to 2028 revenue of about $190 billion to $200 billion. A $2 trillion mark would be more than double the $965 billion post-money valuation set when Anthropic raised $65 billion in Series H financing that closed on May 28, 2026. It would also sit above SpaceX’s roughly $1.77 trillion valuation at its June 2026 debut.
Related contracts show how traders are slicing that number. Moonberg put the median first-day closing market cap, given an IPO, near $2.1 trillion, with at least $2.0 trillion near 65% and at least $2.5 trillion near 15%. CryptoNews described a similar cluster, with the $2.0 trillion to $2.25 trillion and $2.25 trillion to $2.5 trillion brackets together holding about 51%. Appetite for a huge debut is real.
What would move Anthropic year-end IPO probability next?
A public S-1 is the next signal to watch. If the prospectus lands and the roadshow starts, November’s lead can firm and the year-end price can hold above 80%. If the document sputters again, December absorbs more of the Yes case, and January starts to matter.
OpenAI is the contrast trade. Mid-September Polymarket pricing put an Anthropic IPO before 2027 near 88%, while an OpenAI listing by the end of 2026 was priced near 4%. Moonberg later put the chance that Anthropic lists before OpenAI near 95%. That gap can narrow if Anthropic’s calendar slips and OpenAI’s does not.
References
- CryptoNews: Anthropic IPO Polymarket odds of a 2026 IPO hit 82%
- Polymarket month odds tracker, updated October 1, 2026
- Polymarket: In which month will Anthropic IPO?
- Moonberg: Anthropic valuation and IPO odds
- CryptoBriefing: Traders see a 57% chance of an Anthropic IPO in November
- TokenPost: Prediction markets put Anthropic’s November IPO odds at 56%
- CoinGape: Will Anthropic IPO by December 31, 2026?
- Anthropic: confidential draft S-1 submitted to the SEC
- IFR: Anthropic supplier liabilities ahead of a potential IPO
- InvestmentNews: IPO filing shows revenue jump and $518 billion compute bill
- TechTimes: prospectus risk language and $2 trillion ask
