Anthropic’s October 26, 2026 S-1 filing, which formally designates Goldman Sachs in the lead-left underwriting position with Morgan Stanley as co-lead and stabilization agent, is the decisive catalyst anchoring the 88% market-implied probability for Goldman Sachs. This disclosure reversed earlier trader consensus favoring Morgan Stanley and aligns with the bank’s prior lead-left role on SpaceX’s June IPO, where it earned top fees within a 22-bank syndicate. The filing also highlights Anthropic’s rapid revenue expansion to $16.3 billion in the first half of 2026 and its planned Nasdaq listing under ticker ANT, potentially the largest IPO on record at up to $100 billion. Other banks, including JPMorgan at 0.6%, remain sidelined as the prospectus order establishes clear hierarchy.
This market will resolve according to the bank that serves as the lead underwriter in the initial public offering of Anthropic. If no IPO occurs by December 31, 2027, 11:59 PM ET, or Anthropic completes an initial public offering without a designated lead underwriter, this market will resolve to “Other.” If multiple banks are identified as lead underwriters, this market will resolve according to the primary lead underwriter. If the hierarchy between them is unclear, this market will resolve once it is conclusively evident which bank is the primary lead underwriter, for example, through the order in which the banks are listed in the underwriting section of Anthropic’s final initial public offering prospectus, once released. The primary resolution source for this market will be official disclosures from Anthropic. A consensus of credible reporting may also be used.