Anthropic IPO tax planner

Part 1 — Settlement tax at the IPO

Part 2 — Hold past one year, or sell at lockup end?

Settlement sets your basis at the IPO price. Gains after that are short-term (ordinary rates) until you've held one year from settlement, long-term after. Enter an assumed future sale price to compare the two treatments on the same gain. Both include the 3.8% NIIT and your state rate.

Method and assumptions

• 2026 federal brackets and long-term capital gains thresholds per IRS Rev. Proc. 2025-32; supplemental withholding 22% up to $1M of supplemental wages, 37% above, per IRS Pub. 15-T.¹
• Long-term gains stack on top of ordinary income across the 0/15/20% thresholds ($545,500 single / $613,700 MFJ for the 20% line). NIIT of 3.8% is applied to the full modeled gain when income exceeds $200K single / $250K MFJ — a simplification of the MAGI test.²
• Ignores deductions, credits, AMT, payroll taxes on the wage side, and state-specific bracket structures (flat rate applied). California taxes gains as ordinary income — 13.3% is the top rate.³ Estimates only; confirm with a CPA.
• Anthropic's actual IPO price, share counts, and lockup terms are not public — this tool runs your scenarios, it doesn't predict them. Context: Anthropic employee guide, the IPO timeline, and the lockup playbook.

The calculator shows the size of the problem. A specialist solves it.

Get matched with a fee-only fiduciary who works IPO equity events — settlement modeling with your real grants, estimated payments, lockup glidepath, 10b5-1 setup. Free, no obligation.