What will Anthropic's public-market capitalization be 90 days after its IPO, in USD billions (conditional on an IPO occurring)?

Conditional on an IPO occurring, I assess Anthropic's 90-day post-IPO market capitalization centered at $1.09T, modestly above its late-May 2026 $965B Series H post-money valuation anthropic.com. This baseline assumes the company retains control over its listing timing, naturally censoring the worst downside scenarios and listing into a reasonably favorable market window, as suggested by its June 1 confidential S-1 filing anthropic.com.

The distribution's right skew (p75 at ~$1.4T, p90 at ~$1.84T) is driven by unprecedented growth metrics and intense market appetite for pure-play frontier AI. Anthropic's run-rate revenue hit ~$47B by mid-May 2026, alongside reports of customer adoption requiring peak-hour rationing reuters.com and massive infrastructure commitments (e.g., up to 5GW with AWS anthropic.com and multi-GW capacity with Google/Broadcom anthropic.com). The recent SpaceX IPO provides the clearest comparable for mega-cap tech appetite: pricing at $1.77T and surging past $2T on its debut reuters.com. If Anthropic's S-1 reveals strong unit economics and AI enthusiasm holds, a sustained re-rating toward $1.8T is highly plausible.

However, a substantial downside tail (p25 at ~$853B, p10 at ~$627B) reflects severe fundamental and regulatory vulnerabilities that could materialize or persist through the 90-day post-IPO window. Chief among these is public market scrutiny of Anthropic's accounting: revenue is booked gross for cloud-reseller spend. If public investors rigorously discount this top-line figure to reflect weak underlying gross margins, the valuation could revert toward the $400-$500B range implied by skeptical private-market passers. Additionally, Anthropic carries unique regulatory overhangs. The June 12 BIS export-control directive forced a global shutdown of the newly launched Fable 5 and Mythos 5 models 2 sources, presenting a novel structural risk to their premium tier. This is compounded by the unresolved Department of War supply-chain-risk designation, with a D.C. Circuit ruling still pending 2 sources. Combined with the broader fragility of the AI sector reuters.com, these factors justify a wide distribution with a 10th percentile dipping well below the Series H mark.