When will Anthropic IPO?

Anthropic is targeting October 2026 per The Information (cited by Forbes May 4, 2026). Goldman Sachs and JPMorgan Chase are lead banks; Wilson Sonsini is legal counsel. A practical timeline implies an S-1 in July or August 2026, a roadshow in September, and pricing in October. Anthropic has not formally committed and has stated it 'has not decided when or even if it will go public.' Expected IPO valuation is $400-500 billion in public-market pricing — below the May 2026 private round at $850-900 billion+.

When will OpenAI IPO?

OpenAI is targeting Q4 2026 with a goal valuation of approximately $1 trillion. Specific dates are less defined than Anthropic's October target. The corporate restructure — capping Microsoft's profit-sharing rights — is the gating item before a formal listing. If OpenAI files in Q3 2026, a November-December 2026 listing is plausible. If the restructure slips, the IPO could push into 2027.

Why are Anthropic's private and IPO valuations so different?

Anthropic's May 2026 private round prices at $850-900 billion+. The IPO target is $400-500 billion. The gap exists because (1) private preferred shares carry liquidation preferences, dividends, and anti-dilution protections that public common stock lacks, (2) IPO valuations are typically conservatively priced to ensure a positive aftermarket pop, and (3) public-market scrutiny applies higher discount rates than private investors do. Public IPO investors are getting a structurally cheaper entry.

What happens if both companies IPO in Q4 2026?

If both Anthropic ($400-500B target) and OpenAI ($1T target) list in Q4 2026, that's roughly $1.5T of new AI float in 60 days — the largest concentrated AI listing event in history. Effects include: market liquidity strain (Q4 IPO calendar typically absorbs $50-100B; this is 15-30x that), pricing pressure on both deals (concentrated supply usually requires lower pricing to clear), and broader market re-rating of AI valuations. SpaceX is also rumored for a 2026 listing, which could compound the supply effect.

Quick Answer

Anthropic vs OpenAI IPO Timeline: Q4 2026 Race (May 2026)

Published: May 5, 2026

Anthropic vs OpenAI IPO Timeline: Q4 2026 Race (May 2026)

Two of the three largest private companies in the world are targeting Q4 2026 IPOs. Anthropic is aiming for October 2026 at $400-500 billion in public-market valuation. OpenAI is targeting Q4 2026 at ~$1 trillion. Together, they would represent roughly $1.5 trillion of new AI float — the largest concentrated AI listing event in history. Here’s how the timing race shapes up as of May 5, 2026.

Last verified: May 5, 2026

The two timelines

Milestone	Anthropic	OpenAI
Bank syndicate	Goldman Sachs, JPMorgan (lead)	TBA
Legal counsel	Wilson Sonsini	TBA
S-1 expected	July-August 2026	Q3 2026
Roadshow	September 2026	Q4 2026
Pricing target	October 2026	November-December 2026
Public valuation target	$400-500B	~$1T
Last private valuation	$850-900B+ (May 2026)	$852B (March 2026)
Gating item	Market conditions	Microsoft restructure
Confirmed?	Reported, not officially committed	Reported, not officially committed

Sources: Forbes “Anthropic’s $900 Billion Funding Round Set To Surpass OpenAI” (May 4, 2026), The Information IPO timing reports (April 2026), Bloomberg News (April 29, 2026), Reuters (April 29, 2026), TechCrunch (April 30, 2026), TradingKey “SpaceX Roadshow as Early as June, OpenAI and Anthropic IPOs in Second Half” (April 2026).

Anthropic’s IPO path

Anthropic has the more concrete public-listing trajectory:

May 2026 private round ($40-50B at $850-900B+) closes in mid-to-late May. This bridge round funds 2026-2027 capex without needing IPO proceeds for working capital.
S-1 filing expected July-August 2026. With Goldman Sachs and JPMorgan Chase as lead banks and Wilson Sonsini as legal counsel, the team is in place. Filing in July-August aligns with a fall listing target.
Roadshow in September 2026. Two- to three-week investor roadshow. Anchor orders from sovereign wealth funds and large asset managers (Fidelity, T. Rowe, BlackRock) typically cover ~60-70% of the deal.
October 2026 pricing. Pricing target of $400-500 billion in public-market valuation. The discount to the May 2026 private round is structural (preferred vs common, IPO discount).
Aftermarket trading. Q4 2026 - Q1 2027 will tell whether the public market re-rates Anthropic up to private-round levels or stays below.

Key risk for Anthropic: Market conditions deteriorate between May and October. The May 2026 private round at $850-900B+ effectively sets a high private benchmark; a public listing meaningfully below that is possible if AI sector sentiment shifts.

OpenAI’s IPO path

OpenAI’s path is more complex due to the Microsoft restructure:

Microsoft profit-sharing cap. OpenAI’s commercial relationship with Microsoft includes profit-sharing rights that need to be restructured before a clean public listing. This is the gating item, and progress has been slower than the Anthropic path.
Q3 2026 S-1 filing if the Microsoft restructure completes. If it slips, the IPO could push into 2027.
Q4 2026 listing (November-December most likely if S-1 files in Q3).
$1 trillion valuation target. Significantly above OpenAI’s last private round ($852B). The $1T target reflects (a) consumer scale (1B+ MAU on ChatGPT), (b) revenue scale ($13B annualized), (c) Microsoft partnership value, and (d) general AI market re-rating expectations.

Key risk for OpenAI: Microsoft restructure slips. If the corporate cleanup isn’t done by end of Q3, the listing pushes to 2027 and the AI capital-markets calendar is materially affected.

Why two IPOs in 60 days matters

If both deals price in Q4 2026, several things happen simultaneously:

1. Liquidity strain. Q4 IPO calendars typically absorb $50-100 billion of new issuance. Anthropic + OpenAI alone could be 15-30x that. SpaceX is also rumored for a 2026 listing (potentially Q3-Q4), which would compound the effect.

2. Pricing pressure on both deals. Concentrated supply usually requires lower pricing to clear, especially when the buyers are largely the same large asset managers. Anthropic going first (October) gives it a pricing advantage; OpenAI (November-December) faces a market that’s already digested Anthropic.

3. Broader AI sector re-rating. Public-market pricing of two flagship AI labs will reset multiples for everything else — Snowflake, Datadog, MongoDB, Palantir, even hyperscalers. The two listings are effectively a referendum on the AI sector’s capital-markets value.

4. Secondary effects on private rounds. AI labs and AI-application startups raising private rounds in late 2026 / early 2027 will price relative to the new public benchmarks. A weak Anthropic / OpenAI aftermarket would compress private-round valuations across the sector.

Investor positioning ahead of the listings

Three patterns are visible in the secondary market:

Pre-IPO secondary buyers paying premium prices. Per Business Insider (April 2026), Anthropic shares trade above $800B on secondary markets, with extreme demand. Some buyers reportedly offering houses for shares.
Early backers selling partial. Per TechCrunch, some pre-2024 Anthropic investors are using the May 2026 private round as a partial liquidity event. This is normal pre-IPO behavior and de-risks individual investor positions.
Index inclusion anticipation. S&P 500 / Russell 1000 index inclusion typically takes 6-12 months post-IPO; early Anthropic / OpenAI buyers face a holding period before passive demand kicks in.

What to watch through 2026

May 2026:

Anthropic May round closes (mid-to-late May).
OpenAI Microsoft restructure progress visible.
AI market sentiment broadly.

Summer 2026:

Anthropic S-1 filing (July-August).
OpenAI S-1 filing (potentially Q3).
Mythos GA (likely positions Anthropic for IPO).

Fall 2026:

Anthropic roadshow (September).
Anthropic pricing (October).
OpenAI roadshow (October-November).
OpenAI pricing (November-December).

Q1 2027:

Aftermarket trading patterns.
Lock-up expirations (typically 180 days).
Index inclusion timing.

Key uncertainties

Three things could disrupt the timeline materially:

Macroeconomic shock. Recession, rate spike, or AI bubble correction could push either or both listings into 2027.
Regulatory action. EU AI Act enforcement, DOJ antitrust scrutiny, or state-level AI laws could affect IPO disclosures and timing.
Operational issues. A model regression, security incident, or major commercial loss for either company could derail the listing.

Comparison to historical AI IPOs

For context:

Company	IPO Date	IPO Valuation
Snowflake	Sept 2020	$33B
Palantir	Sept 2020	$21B
Cloudflare	Sept 2019	$4.5B
CoreWeave	March 2025	$23B
Anthropic (target)	Oct 2026	$400-500B
OpenAI (target)	Q4 2026	~$1T

Anthropic’s target valuation is roughly 10x Snowflake’s IPO. OpenAI’s target is roughly 30x. These would be by far the largest tech IPOs in history.

Bottom line

In May 2026, both Anthropic and OpenAI are targeting Q4 2026 IPOs at $400-500B and ~$1T respectively. Anthropic’s path is more defined — Goldman Sachs, JPMorgan, October target. OpenAI’s path is gated by the Microsoft restructure. If both happen as planned, $1.5T of new AI float in 60 days is unprecedented and will reset the entire AI capital-markets stack. For enterprise buyers and developers, IPOs don’t change the products — but they do change long-term sustainability calculus and signal that the major AI labs are now generationally important public companies.

Sources: Forbes “Anthropic’s $900 Billion Funding Round Set To Surpass OpenAI” (May 4, 2026), The Information IPO timing reports (April 2026), Reuters “Anthropic weighs new funding round at valuation exceeding $900 billion” (April 29, 2026), TechCrunch “Anthropic potential $900B+ valuation round could happen within 2 weeks” (April 30, 2026), TradingKey SpaceX/OpenAI/Anthropic IPO analysis (April 2026), TechMarketBriefs Anthropic IPO analysis, MarketWise Anthropic IPO 2026 analysis.