IPO Summer 2026: Anthropic, OpenAI, and the Race to Price Artificial Intelligence on Public Markets

With SpaceX now public, Anthropic has confidentially filed at a ~$965 billion valuation and OpenAI follows at $852 billion. We break down what their IPOs mean for public markets, AI competition, and investors.

Key Takeaways

• Anthropic confidentially filed its S-1 with the SEC on June 1, 2026; OpenAI followed on June 8
• Anthropic’s latest funding values it at approximately $965 billion; OpenAI targets a $852 billion debut valuation
• Anthropic’s annualised revenue run rate crossed $44–47 billion in May 2026, growing at roughly 10x per year
• Both Goldman Sachs and Morgan Stanley are bookrunning both deals, each expected to raise at least $60 billion
• Together with SpaceX, the three mega-IPOs could demand north of $200 billion from public markets in 2026

The Year Public Markets Had to Price AGI

SpaceX’s June 12 debut was historic. But in the longer narrative arc of 2026, it may prove to be the prelude. With Elon Musk’s rocket company now trading on the Nasdaq and raising $85.7 billion in the largest IPO in history, Wall Street’s attention has pivoted immediately to the next act: Anthropic and OpenAI, the two companies whose products are reshaping global knowledge work, coding, legal services, healthcare, and finance — and whose valuations are asking public markets to price something it has never priced before: the plausible path to artificial general intelligence.

The sequence is moving fast. Anthropic confidentially filed its S-1 with the SEC on June 1, 2026, the company confirmed in a blog post that day (Fortune, June 1, 2026). OpenAI followed exactly one week later, on June 8, announcing its own filing rather than allowing it to leak — a signal from Sam Altman’s team that they intend to control the IPO narrative (FutureSearch, June 2026). Both are bookrun by the same dual-bank syndicate: Goldman Sachs and Morgan Stanley, each expected to raise at least $60 billion (FutureSearch).

Anthropic: The Quiet Frontrunner

Twelve months ago, Anthropic was universally described as OpenAI’s challenger. Today, by several key metrics, it has pulled ahead. The company’s annualised revenue run rate crossed $44–47 billion in May 2026, compounding at approximately 10x per year — a growth rate that makes OpenAI’s roughly 3.4x annualised growth look almost conventional by comparison (IndMoney, June 2026; BitMEX).

Anthropic raised $30 billion in a Series G round in February 2026 at a $380 billion post-money valuation, before a $65 billion Series H-1 round in May pushed the private valuation to approximately $965 billion — eclipsing OpenAI’s valuation for the first time (Fortune, June 2026). The company is also on track to post its first-ever operating profit in Q2 2026, projecting approximately $559 million on $10.9 billion in quarterly revenue (IndMoney).

The enterprise thesis is central to Anthropic’s public market story. Approximately 80% of revenue comes from enterprise customers, and Anthropic’s share of the enterprise AI market surpassed OpenAI’s for the first time in April 2026, driven by Claude’s dominance in agentic coding workflows, legal research, and financial analysis (IG UK, June 2026). Anthropic has told investors its annualised run rate will surpass $50 billion by July, and has projected $70 billion in revenue with $17 billion in free cash flow by 2028 (IG UK).

The risks are real. A $5.6 billion net loss in 2024 and a 2028 cash-flow profitability target — rather than an immediate one — mean investors must take a long-dated view. The company is also embroiled in a legal dispute with the U.S. government after the Pentagon designated it a supply-chain risk, a designation Anthropic argues could jeopardise billions in revenue (Fortune). Additionally, a June 12 regulatory action suspending the “Claude Fable” model export has widened the tail risk on Anthropic’s IPO timeline, pushing the p10 downside date out to April 2028 in some analyst models (FutureSearch).

The consensus target date for Anthropic’s listing is December 2026, with a first-day market cap median of approximately $1.10 trillion — which would make it the first pure-enterprise AI safety company to trade publicly, and one of the most valuable companies ever to debut (FutureSearch).

OpenAI: Bigger by Brand, Smaller by Growth Rate

OpenAI carries extraordinary brand recognition — ChatGPT crossed 900 million weekly active users by early 2026 — and its revenue trajectory, while slower than Anthropic’s in percentage terms, is still formidable in absolute terms: revenues grew from approximately $2 billion annualised in 2023 to over $20 billion by end-2025 (IndMoney).

But the loss picture gives public investors pause. FutureSearch estimates OpenAI’s 2026 GAAP net loss at $25–26 billion against a widely cited $14 billion non-GAAP figure — a gap that reflects the difference between the story management is telling on the roadshow and the financial reality a public company must disclose in quarterly filings (FutureSearch). The 90-day post-IPO market cap estimate of $0.86 trillion — materially below the first-day median — reflects the prediction that institutional models, once they have time to fully digest the loss line, will price more conservatively than day-one narrative demand.

OpenAI’s $852 billion debut valuation target positions it slightly below Anthropic’s pre-IPO mark (Fortune, June 2026). The later it lists, the more revenue compounds under the number — meaning OpenAI has a structural incentive to maximise quality of disclosure ahead of its September target rather than rush to beat Anthropic to market.

The Capital Markets Challenge: Can the System Absorb It?

The scale of capital being demanded is genuinely unprecedented. SpaceX alone raised $85.7 billion. Anthropic and OpenAI are each expected to raise at least $60 billion. Total 2026 U.S. IPO proceeds could reach approximately $160 billion, according to Goldman Sachs projections — against a 2025 baseline of $45 billion (IndMoney).

The liquidity case is that there is an estimated $8 trillion sitting in U.S. money market funds. SpaceX’s $85.7 billion raise represents roughly 1% of that pool. Institutional investors who have spent years gaining AI exposure indirectly — via Nvidia for chips, Microsoft for its OpenAI stake, Alphabet for its Anthropic investment — now have the option of owning the underlying models directly. The pent-up demand for pure-play AI exposure is enormous.

The displacement risk is subtler but real. Money rotating into SpaceX, Anthropic, and OpenAI must come from somewhere — and that somewhere is likely existing Magnificent 7 positions or cash allocations that would otherwise flow into other sectors (IndMoney). The portfolio rebalancing triggered by three mega-listings could create meaningful headwinds for established large-cap tech stocks in the second half of 2026.

The Race to First-Mover Advantage

Anthropic’s decision to file first was strategically deliberate. By going to market ahead of OpenAI, the company avoids being overshadowed by its more famous rival and benefits from scarcity — institutional investors who buy Anthropic have less capital available for OpenAI when it comes. OpenAI, meanwhile, gains a tactical advantage from watching how the market prices audited frontier AI financials before committing to its own price.

It is worth noting, as IG UK observes, that both companies filed within days of each other despite being direct competitors — suggesting that both management teams made independent calculations that the post-SpaceX IPO window represents an optimal moment for AI listings, when investor appetite for frontier technology is at a verifiable high and the SpaceX roadshow has done the work of educating institutional allocators on how to think about pre-profitability, mission-driven, deeply moated technology businesses (IG UK).

2026: The Year That Changes Public Markets Forever

If SpaceX, Anthropic, and OpenAI all complete their listings before year-end, 2026 will be remembered as the year public markets were forced to price artificial general intelligence for the first time. Their combined target valuations of approximately $3.6 trillion equal the GDP of France — and they are not asking investors to value what they earn today, but what humanity becomes tomorrow (IndMoney).

That is a proposition without precedent in the history of capital markets. Whether public markets accept it enthusiastically, price it conservatively, or — as some veteran investors warn — create the conditions for a correction of historic proportions when the gap between narrative and quarterly earnings becomes undeniable, is the central investment question of 2026.