Anthropic insiders may sell up to 10% of locked-up shares on IPO day

Anthropic’s IPO paperwork reportedly includes an unusual perk for some insiders. Certain shareholders may be able to sell up to 10% of their locked-up shares on the very first day of trading.

What the filing reportedly allows

The AI company behind the Claude models submitted a draft Form S-1 registration to the SEC on June 1, 2026. An S-1 is the formal document a company files before selling shares to the public.

According to reports on the filing, some insiders could unload up to 10% of their locked-up holdings when the stock debuts. That provision reportedly comes paired with longer-than-usual lockup agreements on the remaining shares.

A lockup is the waiting period after an IPO during which early investors and employees can’t sell. It exists to stop a flood of insider selling from swamping a freshly listed stock.

The approach marks a departure from the playbook used by other high-profile tech listings, including SpaceX, according to the research findings.

The timeline and the price tag

The draft filing is only the opening act. A public version of the S-1 is expected between October 23 and 26, 2026.

From there, the IPO roadshow is slated to begin around November 9. Trading could start before Thanksgiving, with the offering anticipated in mid-to-late November 2026.

The numbers attached to all this are large. Anthropic hit a $965 billion post-money valuation in its May 2026 private funding round.

Discussions around the IPO suggest target valuations could land somewhere between $1.5 trillion and $2 trillion.

Projections put 2025 revenue at approximately $4.6 billion, which the research describes as a twelvefold increase from prior results.

Reports also indicate that first-half 2026 revenue might be as high as $16.3 billion.

The costs are equally eye-catching. Losses for 2025 are projected at around $42 billion, and the company’s compute commitments for AI infrastructure exceed $500 billion.

What this means for investors

For anyone watching the offering, the lockup mechanics are worth as much attention as the headline valuation. The reported 10% window sets a ceiling on how much insider stock can hit the market on day one.

The bigger questions will likely surface when the public S-1 arrives in late October. That filing is expected to detail governance, revenue expectations and risk factors, including issues tied to AI safety and how much the company relies on key customers.