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icon for Anthropic or OpenAI: higher IPO closing market cap?

Anthropic or OpenAI: higher IPO closing market cap?

icon for Anthropic or OpenAI: higher IPO closing market cap?

Anthropic or OpenAI: higher IPO closing market cap?

Anthropic

81% chance
Polymarket
NEW

Anthropic

81% chance
Polymarket
NEW
This market will resolve to "Anthropic" if the official closing price for Anthropic's market capitalization on its first trading day is above the official closing price for OpenAI's market capitalization on its first trading day. This market will resolve to "OpenAI" if the official closing price for OpenAI's market capitalization on its first trading day is above the official closing price for Anthropic's market capitalization on its first trading day. This market will resolve to the company that completes an Initial Public Offering (IPO) by December 31, 2028, 11:59 PM ET, if the other company does not complete an IPO within the market timeframe. This market will resolve to the IPOed company as soon as it becomes impossible for the other company to complete an IPO within the market timeframe, including due to acquisition, merger, or absorption by an entity that is already publicly traded. This market will resolve 50-50 if: - Neither IPO occurs by December 31, 2028, 11:59 PM ET. - Both Anthropic and OpenAI complete an IPO within this market's timeframe, and their IPO closing market capitalizations are exactly equal. - Both companies become unable to complete an IPO, including due to acquisition, merger, or absorption by an entity that is already publicly traded. Market capitalization expresses the monetary value of a company’s outstanding shares, stated in its pricing currency. It is calculated as the total number of outstanding shares, multiplied by the official closing share price of the publicly traded class on the first trading day. If necessary, to accurately capture the company’s total market capitalization, rather than a stock-class-specific market capitalization, the calculation will include all outstanding share classes and apply any stated conversion ratios to the publicly traded class. Where no conversion right exists, such shares will be counted at their stated outstanding amount without discount, unless official filings explicitly specify differently. The number of outstanding shares will be determined from official company filings or disclosures (e.g., SEC filings). The closing share price on the first trading day will be determined from the primary exchange’s official listing page. In the event of an interruption in the normal trading session on the specified company’s first day of trading (e.g., a circuit breaker or half-day), the market will resolve according to the official closing price of the abbreviated session. If no such official closing price is published, the market will resolve according to the next trading day on which an official closing price is published, treating that day as the first day of trading for the purposes of this market.Anthropic’s surge past OpenAI in private valuation and revenue momentum is the main factor underpinning the 68.5% market-implied odds that it will close its IPO at a higher market cap. In May 2026, Anthropic closed a $65 billion Series H round at a $965 billion post-money valuation with a $47 billion annualized revenue run rate, eclipsing OpenAI’s $852 billion March valuation and lower estimated run rate. Both companies filed confidential S-1s in June, but Anthropic is advancing toward an October listing with investor targets exceeding $2 trillion, while OpenAI has signaled a possible 2027 debut amid slower progress on meetings and filings. These developments in funding scale, revenue trajectory, and IPO timing have driven trader consensus on Anthropic’s edge at public-market debut.

This market will resolve to "Anthropic" if the official closing price for Anthropic's market capitalization on its first trading day is above the official closing price for OpenAI's market capitalization on its first trading day.

This market will resolve to "OpenAI" if the official closing price for OpenAI's market capitalization on its first trading day is above the official closing price for Anthropic's market capitalization on its first trading day.

This market will resolve to the company that completes an Initial Public Offering (IPO) by December 31, 2028, 11:59 PM ET, if the other company does not complete an IPO within the market timeframe. This market will resolve to the IPOed company as soon as it becomes impossible for the other company to complete an IPO within the market timeframe, including due to acquisition, merger, or absorption by an entity that is already publicly traded.

This market will resolve 50-50 if:
- Neither IPO occurs by December 31, 2028, 11:59 PM ET.
- Both Anthropic and OpenAI complete an IPO within this market's timeframe, and their IPO closing market capitalizations are exactly equal.
- Both companies become unable to complete an IPO, including due to acquisition, merger, or absorption by an entity that is already publicly traded.

Market capitalization expresses the monetary value of a company’s outstanding shares, stated in its pricing currency.

It is calculated as the total number of outstanding shares, multiplied by the official closing share price of the publicly traded class on the first trading day.

If necessary, to accurately capture the company’s total market capitalization, rather than a stock-class-specific market capitalization, the calculation will include all outstanding share classes and apply any stated conversion ratios to the publicly traded class. Where no conversion right exists, such shares will be counted at their stated outstanding amount without discount, unless official filings explicitly specify differently.

The number of outstanding shares will be determined from official company filings or disclosures (e.g., SEC filings). The closing share price on the first trading day will be determined from the primary exchange’s official listing page.

In the event of an interruption in the normal trading session on the specified company’s first day of trading (e.g., a circuit breaker or half-day), the market will resolve according to the official closing price of the abbreviated session. If no such official closing price is published, the market will resolve according to the next trading day on which an official closing price is published, treating that day as the first day of trading for the purposes of this market.
Volume
$0
End Date
Dec 31, 2028
Market Opened
Aug 19, 2026, 12:23 PM ET
This market will resolve to "Anthropic" if the official closing price for Anthropic's market capitalization on its first trading day is above the official closing price for OpenAI's market capitalization on its first trading day. This market will resolve to "OpenAI" if the official closing price for OpenAI's market capitalization on its first trading day is above the official closing price for Anthropic's market capitalization on its first trading day. This market will resolve to the company that completes an Initial Public Offering (IPO) by December 31, 2028, 11:59 PM ET, if the other company does not complete an IPO within the market timeframe. This market will resolve to the IPOed company as soon as it becomes impossible for the other company to complete an IPO within the market timeframe, including due to acquisition, merger, or absorption by an entity that is already publicly traded. This market will resolve 50-50 if: - Neither IPO occurs by December 31, 2028, 11:59 PM ET. - Both Anthropic and OpenAI complete an IPO within this market's timeframe, and their IPO closing market capitalizations are exactly equal. - Both companies become unable to complete an IPO, including due to acquisition, merger, or absorption by an entity that is already publicly traded. Market capitalization expresses the monetary value of a company’s outstanding shares, stated in its pricing currency. It is calculated as the total number of outstanding shares, multiplied by the official closing share price of the publicly traded class on the first trading day. If necessary, to accurately capture the company’s total market capitalization, rather than a stock-class-specific market capitalization, the calculation will include all outstanding share classes and apply any stated conversion ratios to the publicly traded class. Where no conversion right exists, such shares will be counted at their stated outstanding amount without discount, unless official filings explicitly specify differently. The number of outstanding shares will be determined from official company filings or disclosures (e.g., SEC filings). The closing share price on the first trading day will be determined from the primary exchange’s official listing page. In the event of an interruption in the normal trading session on the specified company’s first day of trading (e.g., a circuit breaker or half-day), the market will resolve according to the official closing price of the abbreviated session. If no such official closing price is published, the market will resolve according to the next trading day on which an official closing price is published, treating that day as the first day of trading for the purposes of this market.
This market will resolve to "Anthropic" if the official closing price for Anthropic's market capitalization on its first trading day is above the official closing price for OpenAI's market capitalization on its first trading day. This market will resolve to "OpenAI" if the official closing price for OpenAI's market capitalization on its first trading day is above the official closing price for Anthropic's market capitalization on its first trading day. This market will resolve to the company that completes an Initial Public Offering (IPO) by December 31, 2028, 11:59 PM ET, if the other company does not complete an IPO within the market timeframe. This market will resolve to the IPOed company as soon as it becomes impossible for the other company to complete an IPO within the market timeframe, including due to acquisition, merger, or absorption by an entity that is already publicly traded. This market will resolve 50-50 if: - Neither IPO occurs by December 31, 2028, 11:59 PM ET. - Both Anthropic and OpenAI complete an IPO within this market's timeframe, and their IPO closing market capitalizations are exactly equal. - Both companies become unable to complete an IPO, including due to acquisition, merger, or absorption by an entity that is already publicly traded. Market capitalization expresses the monetary value of a company’s outstanding shares, stated in its pricing currency. It is calculated as the total number of outstanding shares, multiplied by the official closing share price of the publicly traded class on the first trading day. If necessary, to accurately capture the company’s total market capitalization, rather than a stock-class-specific market capitalization, the calculation will include all outstanding share classes and apply any stated conversion ratios to the publicly traded class. Where no conversion right exists, such shares will be counted at their stated outstanding amount without discount, unless official filings explicitly specify differently. The number of outstanding shares will be determined from official company filings or disclosures (e.g., SEC filings). The closing share price on the first trading day will be determined from the primary exchange’s official listing page. In the event of an interruption in the normal trading session on the specified company’s first day of trading (e.g., a circuit breaker or half-day), the market will resolve according to the official closing price of the abbreviated session. If no such official closing price is published, the market will resolve according to the next trading day on which an official closing price is published, treating that day as the first day of trading for the purposes of this market.Anthropic’s surge past OpenAI in private valuation and revenue momentum is the main factor underpinning the 68.5% market-implied odds that it will close its IPO at a higher market cap. In May 2026, Anthropic closed a $65 billion Series H round at a $965 billion post-money valuation with a $47 billion annualized revenue run rate, eclipsing OpenAI’s $852 billion March valuation and lower estimated run rate. Both companies filed confidential S-1s in June, but Anthropic is advancing toward an October listing with investor targets exceeding $2 trillion, while OpenAI has signaled a possible 2027 debut amid slower progress on meetings and filings. These developments in funding scale, revenue trajectory, and IPO timing have driven trader consensus on Anthropic’s edge at public-market debut.

This market will resolve to "Anthropic" if the official closing price for Anthropic's market capitalization on its first trading day is above the official closing price for OpenAI's market capitalization on its first trading day.

This market will resolve to "OpenAI" if the official closing price for OpenAI's market capitalization on its first trading day is above the official closing price for Anthropic's market capitalization on its first trading day.

This market will resolve to the company that completes an Initial Public Offering (IPO) by December 31, 2028, 11:59 PM ET, if the other company does not complete an IPO within the market timeframe. This market will resolve to the IPOed company as soon as it becomes impossible for the other company to complete an IPO within the market timeframe, including due to acquisition, merger, or absorption by an entity that is already publicly traded.

This market will resolve 50-50 if:
- Neither IPO occurs by December 31, 2028, 11:59 PM ET.
- Both Anthropic and OpenAI complete an IPO within this market's timeframe, and their IPO closing market capitalizations are exactly equal.
- Both companies become unable to complete an IPO, including due to acquisition, merger, or absorption by an entity that is already publicly traded.

Market capitalization expresses the monetary value of a company’s outstanding shares, stated in its pricing currency.

It is calculated as the total number of outstanding shares, multiplied by the official closing share price of the publicly traded class on the first trading day.

If necessary, to accurately capture the company’s total market capitalization, rather than a stock-class-specific market capitalization, the calculation will include all outstanding share classes and apply any stated conversion ratios to the publicly traded class. Where no conversion right exists, such shares will be counted at their stated outstanding amount without discount, unless official filings explicitly specify differently.

The number of outstanding shares will be determined from official company filings or disclosures (e.g., SEC filings). The closing share price on the first trading day will be determined from the primary exchange’s official listing page.

In the event of an interruption in the normal trading session on the specified company’s first day of trading (e.g., a circuit breaker or half-day), the market will resolve according to the official closing price of the abbreviated session. If no such official closing price is published, the market will resolve according to the next trading day on which an official closing price is published, treating that day as the first day of trading for the purposes of this market.
Volume
$0
End Date
Dec 31, 2028
Market Opened
Aug 19, 2026, 12:23 PM ET
This market will resolve to "Anthropic" if the official closing price for Anthropic's market capitalization on its first trading day is above the official closing price for OpenAI's market capitalization on its first trading day. This market will resolve to "OpenAI" if the official closing price for OpenAI's market capitalization on its first trading day is above the official closing price for Anthropic's market capitalization on its first trading day. This market will resolve to the company that completes an Initial Public Offering (IPO) by December 31, 2028, 11:59 PM ET, if the other company does not complete an IPO within the market timeframe. This market will resolve to the IPOed company as soon as it becomes impossible for the other company to complete an IPO within the market timeframe, including due to acquisition, merger, or absorption by an entity that is already publicly traded. This market will resolve 50-50 if: - Neither IPO occurs by December 31, 2028, 11:59 PM ET. - Both Anthropic and OpenAI complete an IPO within this market's timeframe, and their IPO closing market capitalizations are exactly equal. - Both companies become unable to complete an IPO, including due to acquisition, merger, or absorption by an entity that is already publicly traded. Market capitalization expresses the monetary value of a company’s outstanding shares, stated in its pricing currency. It is calculated as the total number of outstanding shares, multiplied by the official closing share price of the publicly traded class on the first trading day. If necessary, to accurately capture the company’s total market capitalization, rather than a stock-class-specific market capitalization, the calculation will include all outstanding share classes and apply any stated conversion ratios to the publicly traded class. Where no conversion right exists, such shares will be counted at their stated outstanding amount without discount, unless official filings explicitly specify differently. The number of outstanding shares will be determined from official company filings or disclosures (e.g., SEC filings). The closing share price on the first trading day will be determined from the primary exchange’s official listing page. In the event of an interruption in the normal trading session on the specified company’s first day of trading (e.g., a circuit breaker or half-day), the market will resolve according to the official closing price of the abbreviated session. If no such official closing price is published, the market will resolve according to the next trading day on which an official closing price is published, treating that day as the first day of trading for the purposes of this market.

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Frequently Asked Questions

"Anthropic or OpenAI: higher IPO closing market cap?" is a prediction market on Polymarket with 2 possible outcomes where traders buy and sell shares based on what they believe will happen. The current leading outcome is "Anthropic or OpenAI: higher IPO closing market cap?" at 81%. Prices reflect real-time crowd-sourced probabilities. For example, a share priced at 81¢ implies that the market collectively assigns a 81% chance to that outcome. These odds shift continuously as traders react to new developments and information. Shares in the correct outcome are redeemable for $1 each upon market resolution.

"Anthropic or OpenAI: higher IPO closing market cap?" is a newly created market on Polymarket, launched on Aug 19, 2026. As an early market, this is your opportunity to be among the first traders to set the odds and establish the market's initial price signals. You can also bookmark this page to track volume and trading activity as the market gains traction over time.

To trade on "Anthropic or OpenAI: higher IPO closing market cap?," browse the 2 available outcomes listed on this page. Each outcome displays a current price representing the market's implied probability. To take a position, select the outcome you believe is most likely, choose "Yes" to trade in favor of it or "No" to trade against it, enter your amount, and click "Trade." If your chosen outcome is correct when the market resolves, your "Yes" shares pay out $1 each. If it's incorrect, they pay out $0. You can also sell your shares at any time before resolution if you want to lock in a profit or cut a loss.

The current frontrunner for "Anthropic or OpenAI: higher IPO closing market cap?" is "Anthropic or OpenAI: higher IPO closing market cap?" at 81%, meaning the market assigns a 81% chance to that outcome. These odds update in real-time as traders buy and sell shares, so they reflect the latest collective view of what's most likely to happen. Check back frequently or bookmark this page to follow how the odds shift as new information emerges.

The resolution rules for "Anthropic or OpenAI: higher IPO closing market cap?" define exactly what needs to happen for each outcome to be declared a winner — including the official data sources used to determine the result. You can review the complete resolution criteria in the "Rules" section on this page above the comments. We recommend reading the rules carefully before trading, as they specify the precise conditions, edge cases, and sources that govern how this market is settled.