Issue founder shares as original-issue stock in a domestic C-corporation and file an 83(b) election within 30 days for unvested shares. Hold qualified small business stock, or QSBS, for over five years to seek full gain exclusion. Time incentive stock options, or ISOs, which are company options with special tax treatment, for qualifying holding periods. Plan early for rollovers, gifts, and state tax limits before exit talks start.
Table of Contents
- Choose a QSBS-ready C-corporation early
- Time 83(b) and ISO clocks correctly
- Handle AMT and replacement QSBS
- Use trusts carefully and watch state rules
Choose a QSBS-ready C-corporation early
According to Carta, QSBS exclusion starts with original-issue stock from a domestic C-corporation Carta's QSBS guide. The company must meet a $50M gross-asset test and an 80% active-business test. The founder must hold shares over five years to exclude 100% of gain up to the greater of $10M or 10x basis.
Check these points before incorporation or first stock issuance: BDO reports higher limits for QSBS acquired after July 4, 2025. The asset cap rises to $75M and the cap to $15M. Tiered exclusion applies at 50% after 3 years, 75% after 4 years, and 100% after 5 years.
- issue founder stock directly from the C-corporation
- keep gross assets below the cap at issuance
- keep most assets and work in active business operations
Time 83(b) and ISO clocks correctly
According to Cooley, a founder with unvested restricted stock can file an 83(b) election within 30 days of grant Cooley's Section 83(b) guide. The election taxes grant-date value as ordinary income and starts the long-term capital-gain clock early. Miss the deadline and each vesting event taxes vesting-date value as ordinary income. The IRS FAQ says qualifying disposition needs holding shares more than two years after grant and more than one year after exercise IRS stock-options FAQ.
Sell earlier and the sale is a disqualifying disposition. That early sale turns the gain into ordinary compensation income. When grant-date value is low, early filing keeps upfront tax small. It also starts capital treatment from day one.
Handle AMT and replacement QSBS
IRS Topic No. 427 explains that exercising ISOs and holding past year-end generally triggers no regular tax. The bargain-element spread still counts as alternative minimum tax income. That spread can create AMT payable now and a later credit against regular tax.
Westlight Wealth reports that Section 1045 helps noncorporate holders who owned QSBS over six months. Buying replacement original-issue QSBS within 60 days defers exit gain. Tax applies only to proceeds above reinvestment, and replacement basis drops accordingly. Exercise in small blocks and model AMT before year-end. Line up replacement QSBS targets before closing a sale.
Use trusts carefully and watch state rules
Boland Law Group describes trust stacking for QSBS. A founder gifts QSBS early to separate non-grantor trusts. A founder plus three trusts may each claim a full per-issuer exclusion when each trust meets original-issuance and other Section 1202 rules.
Withum notes Treasury officials said in May 2026 they are preparing guidance curbing QSBS trust-stacking abuse Withum's Treasury scrutiny update. California and similar states do not conform to the federal exclusion or Section 1045 rollover. Build exit models with both federal and state tax.