Polymarket and Myriad Traders Now Overwhelmingly Favor Anthropic
Prediction markets are becoming remarkably one-sided over which of the two largest private artificial intelligence companies will reach public markets first, with traders now overwhelmingly betting that Anthropic will complete an IPO before OpenAI.
Polymarket currently gives Anthropic roughly a 94% probability of going public before its larger rival, compared with only about 6% for OpenAI. More than $358,000 has been traded in the market, which resolves based on which company completes an IPO first through the end of 2027.
The signal is not confined to one platform.
Myriad currently prices Anthropic at approximately 91% to IPO before OpenAI, against roughly 9% for OpenAI. The market has attracted more than $11,000 in volume.
Kalshi is asking a slightly different question but points in the same direction. Its market on when Anthropic will officially announce an IPO places the probability of an announcement before Nov. 1 at around 70% to 72%. More than $2 million has traded across the Anthropic IPO-date contracts.
The divergence has widened sharply as the companies’ public trajectories have separated.
Anthropic confidentially filed IPO paperwork with U.S. regulators in June and has continued preparations for a public offering. Recent reporting indicates that the Claude developer intends to list on Nasdaq and could move toward an offering later this fall.
The company has also been giving prospective investors a closer look at its financial performance. Anthropic has told investors it expects positive adjusted operating income for a second consecutive quarter, while its revenue has expanded rapidly as enterprise adoption of Claude accelerates.
OpenAI has moved in the opposite direction.
CEO Sam Altman said this weekend that OpenAI will not go public in 2026 as the company focuses on safety concerns surrounding increasingly capable artificial intelligence systems. That reinforced earlier expectations that an OpenAI listing was shifting into 2027.
Prediction markets responded accordingly.
Polymarket’s contract on whether OpenAI will complete an IPO by Dec. 31 now trades at only about 4% to 5%, down from roughly 9% in earlier snapshots. Nearly $1 million has traded on the December deadline alone.
A separate Polymarket market effectively prices the opposite outcome even more aggressively, putting the probability of no OpenAI IPO by the end of 2026 near 98%.
The changing probabilities illustrate how quickly prediction markets can reprice around new information. Unlike conventional analyst forecasts, traders can immediately put capital behind their view as corporate developments emerge.
But IPO markets introduce a particularly sensitive market-integrity issue because the underlying event is inherently information-heavy.
Employees, executives, investment bankers, lawyers, auditors, exchange officials and regulators can all potentially know material details about an IPO process before they become public. Those details can include confidential filings, roadshow dates, exchange selections, pricing discussions, delays and decisions to abandon an offering entirely.
That makes IPO prediction markets structurally different from broad macroeconomic bets where most participants are working from broadly available data.
Concerns over information advantages are already becoming a major issue for the prediction-market sector. European regulators recently warned about insider trading and manipulation in event markets as activity expands across platforms such as Polymarket and Kalshi.
The risk is no longer hypothetical.
The CFTC recently ordered a former White House teleprompter operator to pay $172,539 after finding that he used advance knowledge of President Donald Trump’s speeches to trade event contracts on Kalshi. The case provided a concrete example of how seemingly narrow nonpublic information can become directly monetizable when a prediction market exists for the relevant event.
The enforcement action involving Kalshi trades based on nonpublic information is particularly relevant to IPO markets because the informational chain around a public listing is far larger than the group of people who see an unreleased presidential speech.
There is currently no evidence that the Anthropic or OpenAI markets are being traded using material nonpublic information, and the current pricing is readily explainable from public developments.
Anthropic is actively preparing for a listing. OpenAI has just publicly ruled one out this year.
That alone can explain why traders are heavily favoring Anthropic.
IPO Markets Could Become Prediction Markets’ Hardest Insider-Trading Test
The interesting part is what happens from here.
A 94% probability does not leave much room for ordinary bullish repricing. If Anthropic continues toward an October or November IPO, the market can gradually creep toward certainty. The more useful signal would be a sudden move in the opposite direction before any public explanation appears.
Imagine a fresh Polymarket wallet arriving with several hundred thousand dollars and aggressively buying OpenAI to IPO first while Anthropic still publicly appears on schedule.
That would be worth investigating.
It would not prove insider trading. A sophisticated investor could simply believe Anthropic’s offering will be delayed by market conditions, regulatory issues, valuation disagreements or the escalating AI-safety debate.
But IPO timing creates an unusually large universe of people who may know the answer before everyone else.
A company can confidentially submit documents to the SEC. Lawyers can know when amendments are being prepared. Banks can know when an investor roadshow is moving. Exchanges can know whether listing preparations are advancing. Senior employees can know that management has decided to postpone.
Prediction markets convert each of those facts into something immediately tradable.
The CFTC case is therefore more important than the amount of money involved. It demonstrates that event contracts can create a direct financial payoff from information that previously might have had little standalone trading value.
That challenge becomes larger as prediction markets themselves become more financially important. Kalshi’s latest securities filings show how much capital is flowing into the sector, with the company reporting more than $1 billion in equity sales while reports have placed potential future valuations substantially higher.
Polymarket is expanding too. Its partnership with Sportradar recently grew to cover more than 20 sports leagues and competitions, reflecting how rapidly prediction markets are becoming mainstream financial and information products rather than niche crypto applications.
Growth makes integrity more important.
A market can tolerate someone having a better macro model. It becomes much harder to defend when a trader may simply know that a confidential board meeting happened yesterday.
The regulatory backdrop is already complicated. Kalshi’s continuing fights with state regulators, including its recent legal setback in Nevada, show that even the basic jurisdictional boundaries surrounding prediction markets remain unsettled.
IPO contracts could force regulators to confront an even harder question: what rules should apply when a market explicitly allows people to monetize knowledge about a securities offering before that knowledge becomes public?
For the moment, the Anthropic-OpenAI market itself does not look mysterious. Public information overwhelmingly favors Anthropic, and traders are pricing exactly that.
The better investigative target is the next abnormal trade.
If a new wallet suddenly takes a large position against the 94% consensus shortly before an unexpected Anthropic delay, confidential filing development or OpenAI acceleration becomes public, the timing would deserve much closer scrutiny than an ordinary political or macro whale.
That is what makes this market worth monitoring even after the outcome appears almost one-sided. At 94%, the headline is no longer that traders think Anthropic will win the IPO race. It is that any well-timed trader willing to make a serious bet on the remaining 6% could become far more interesting than the consensus itself.
Shane Neagle is a financial markets analyst and digital assets journalist specializing in cryptocurrencies, memecoins, prediction markets, and blockchain-based financial systems. His work focuses on market structure, incentive design, liquidity dynamics, and how speculative behavior emerges across decentralized platforms.
He closely covers emerging crypto narratives, including memecoin ecosystems, on-chain activity, and the role of prediction markets in pricing political, economic, and technological outcomes. His analysis examines how capital flows, trader psychology, and platform design interact to create rapid market cycles across Web3 environments.
Alongside digital assets, Shane follows broader fintech and online trading developments, particularly where traditional financial infrastructure intersects with blockchain technology. His research-driven approach emphasizes understanding why markets behave the way they do, rather than short-term price movements, helping readers navigate fast-evolving crypto and speculative markets with clearer context.