On Monday, Sam Altman’s AI tech giant, OpenAI, filed for an Initial Public Offering (IPO) in the U.S. behind closed doors. 

This news comes soon after the ChatGPT maker’s competitor, Anthropic, announced it was filing for an IPO with the US Securities and Exchange Commission (SEC) on June 1, 2026. The IPO was filed weeks after raising $65 billion in a funding round that valued it at $965 billion.

OpenAI didn’t reveal the size or terms of the offering, nor did it provide a timeline for its IPO. In an official announcement, the AI giant stated that it may be a while before they announce the timeline because “there are things we want to do that are likely easier as a private company.”

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“But it’s a complicated set of tradeoffs, and this gives us the option to go public sooner if that ends up being best,” the statement added.

Reuters reported that OpenAI is targeting a valuation of up to $1 trillion, and a source indicated that an IPO could come as early as September 2026.

Both rivals targeting the US stock market filed for the IPO privately. This means that their financial summaries are not entirely publicised. The AI giants' underwriters are Goldman Sachs and Morgan Stanley, leading the charge in mega-cap tech listings following the AI boom. 

Also Read: Anthropic's IPO Filing Signals a New Era of Enterprise AI Competition

OpenAI, Anthropic, SpaceX IPO to Fuel Investor AI Appetite

Currently, it seems that investors wish to participate in the AI growth period, drawing them to the public markets. 

With SpaceX planning to go public as soon as this week on June 12, 2026, Elon Musk’s private spaceflight, telecommunications, and AI company plans to break records with its IPO listing of $1.8 trillion — which would make it the largest IPO in history.

OpenAI, Anthropic, SpaceX IPO to Fuel Investor AI Appetite

In May, a US jury ruled against Elon Musk's lawsuit, clearing a major legal barrier for OpenAI's stock market launch. Analysts also pointed out a timing issue, noting that "what OpenAI does not want is for the public market capital to exhaust itself."

The ChatGPT owner’s public filing could unveil its real revenue and profits for the first time, putting its valuation to the test against rivals. 

SpaceX is also expected to launch with a $1.75 trillion valuation, meaning three of the most closely watched tech companies could all go public within months of each other. 

This concentration of high-stakes offerings is something the markets haven’t experienced since the dot-com boom.

Also Read: SpaceX's $75B IPO Could Expedite Enterprise Connectivity & Edge AI Adoption

OpenAI Growing 4X Faster Than Google and Meta

AI has quickly become the paramount investment theme of the decade, first with SpaceX’s IPO and now with both Anthropic and OpenAI public offerings. 

OpenAI announced earlier this year that it was raising $110 billion, reaching an $840 billion valuation, with support from major investors like SoftBank (9984.T), Amazon (AMZN.O), and Nvidia (NVDA.O). 

At that time, it also revealed that ChatGPT had more than 900 million weekly active users and over 50 million consumer subscribers.

OpenAI has had a few backers in the past year, including Microsoft, Amazon and Alphabet’s Google.

Earlier this year, the creator of ChatGPT said it was yielding profits of $2 billion in monthly revenue, according to Reuters. The AI tech large enterprise seems to be growing about four times faster than firms of the internet and mobile eras such as Alphabet and Meta.