On what date will Anthropic complete its IPO (i.e., its shares begin trading on a public stock exchange)?

Status Quo and the October Target. Anthropic is advancing rapidly through the IPO pipeline, having confidentially submitted a draft Form S-1 on June 1, 2026, following a $65B Series H at a $965B post-money valuation anthropic.com. Reporting points consistently to an October 2026 listing, with Goldman Sachs, JPMorgan, and Morgan Stanley leading early "test-the-waters" investor meetings 3 sources. Anthropic’s recently disclosed preliminary Q2 revenue of >$11.5B (roughly 14x YoY) with positive adjusted operating income provides a compelling growth narrative 2 sources. Prediction markets reflect significant optimism, pricing an October listing at over 70% polymarket.com. However, as of mid-August, no publicly "flipped" S-1 has appeared, no official price range is set, and valuation has not been formally discussed with investors cnbc.com.

Timeline Mechanics. Procedurally, resolution occurs on the first day of public trading, not merely at pricing or S-1 effectiveness. SEC rules require the registration statement to be public at least 15 days before the roadshow begins sec.gov. With a standard roadshow lasting one to two weeks before bookbuilding, pricing, and the subsequent morning debut 2 sources, the timeline from public flip to trading is roughly four weeks. Given the lack of a public S-1 as of August 17, a late September or early October debut leaves almost no slack. An October launch remains technically feasible if the prospectus goes public by mid-September, but typical bureaucratic and market frictions often stretch these tight schedules for deals of this scale.

Friction and Delay Risks. Three significant overhangs threaten to push the timeline late into Q4 or beyond. First, gross-versus-net revenue accounting disputes are highly scrutinized by the SEC; Anthropic reportedly books cloud partnership revenue gross, while peers like OpenAI report net 2 sources. Resolving this could require extensive disclosure changes or restatements of ARR metrics. Second, ongoing litigation with the Department of War over an unprecedented "supply chain risk" designation limits U.S. military contracting and requires sensitive, unresolved risk-factor disclosures 3 sources. Finally, the sought-after $2T+ valuation demands a staggering $190–200B revenue forecast for 2028, which may face pushback given recent tech-stock volatility and AI capex scrutiny 2 sources. SpaceX's recent post-IPO dip and OpenAI's deferral to 2027 explicitly due to market choppiness show that mega-issuers are sensitive to market conditions cnbc.com.

Distribution Outlook. Balancing the aggressive October target against structural realities and disclosure hurdles places the median estimate in early November. This accounts for the high probability that complex accounting and litigation issues cause minor slippage past October, while still capitalizing on the active momentum and current open mega-cap IPO window. If the offering misses the pre-Thanksgiving window, calendar friction—specifically the SEC practice of waiting for full-year audited financials after mid-December—typically creates a natural gap, pushing the listing into the late-January to March 2027 window. This structural delay explains the spread to a late-January 75th percentile and a long right tail stretching into late 2027 to account for the risk of a prolonged AI-market downturn or extended regulatory negotiations.