The AMT Trap (The Bankruptcy Maker)

The Most Dangerous Acronym in Tech

The Alternative Minimum Tax (AMT) is a parallel tax system that runs alongside the regular income tax system. Congress created it to prevent wealthy individuals from using deductions and preferences to pay zero tax. The mechanism: the IRS calculates your tax liability twice — once under the regular system, once under AMT rules — and you pay whichever is higher.

For most people, AMT is irrelevant. For engineers exercising ISOs at a high-growth startup, it is a financial landmine.

How AMT Applies to ISO Exercise

Under regular tax rules, exercising an ISO creates no taxable income. Under AMT rules, the spread at exercise is treated as an AMT preference item — phantom income that exists only for AMT calculation purposes. You never received this money. You cannot spend it. But the IRS taxes it anyway.

The Horror Scenario (Based on Real 2000 and 2022 Cases):

1. You exercise 100,000 ISOs with a $1 strike price when the FMV is $11. Spread = $1,000,000.
2. Regular tax: $0 (ISO benefit).
3. AMT calculation: $1,000,000 × 28% AMT rate = $280,000 owed in cash by April 15.
4. You hold the shares, expecting the IPO. The company's valuation collapses. Stock is now worth $0.50/share.
5. You still owe the IRS $280,000. The stock cannot be sold for enough to cover it.
6. Result: Personal bankruptcy. This is not hypothetical — it happened to thousands of engineers during the 2000 dot-com crash and again during the 2022 tech downturn.

The AMT Credit (Partial Relief)

AMT paid is not entirely lost. It converts to an AMT credit that can offset future regular tax liability in years when your regular tax exceeds your AMT. But this only helps if you have future high-income years — and it does nothing if you owe $280k now and have no cash.

The Fix — Four Rules:

1. Never exercise ISOs without running an AMT projection first. A CPA who specializes in tech equity can model your exact AMT exposure before you commit.
2. Exercise early in the year. This gives you until December 31 to assess whether the stock has dropped, and potentially execute a "disqualifying disposition" (sell the shares before year-end) to eliminate the AMT liability — at the cost of losing the ISO tax benefit.
3. Exercise in tranches. You can often exercise a portion of your ISOs each year, staying below the AMT threshold, rather than exercising everything at once.
4. Use the 83(b) election for early exercise. If your company allows early exercise (buying unvested shares), filing an 83(b) election within 30 days of grant locks in a near-zero FMV spread, eliminating both AMT and ordinary income exposure at exercise.