QSBS §1202: The $15M Tax Exclusion Most C-Corp Founders Have Never Checked

What QSBS is

Section 1202 of the Internal Revenue Code — commonly called the Qualified Small Business Stock (QSBS) exclusion — allows qualifying shareholders to exclude up to $15 million (or 15× their adjusted basis, whichever is greater, for shares issued after July 4, 2025) of gain from federal taxable income when they sell C-corp stock that meets all requirements. For shares issued before July 4, 2025, the cap is $10 million (or 10× basis). This is a full exclusion — not a reduced rate, not a deferral. Qualifying gain simply does not appear in federal taxable income at all.

For a founder or early investor who holds qualifying stock worth $10M+ more than they paid for it, this is the single most valuable tax provision available at exit. Most owners who would qualify have never been asked whether they do.

The C-corp entity requirement

This is the central gate. The stock must have been issued by a domestic C-corporation at the time of issuance. S-corps, LLCs, and partnerships are categorically ineligible — not because of how they operate, but because of their tax classification at the moment the stock was issued.

This is the primary reason venture-backed startups elect C-corp status from formation: it preserves QSBS eligibility for founders and investors. An S-corp that later converts to C-corp can issue new qualifying shares after the conversion date, but shares issued while the entity was taxed as an S-corp do not retroactively qualify for §1202.

The holding period requirement

For shares issued after July 4, 2025 (Pub. L. 119-21), tiered exclusions apply based on hold period: 50% exclusion after three years, 75% after four years, and the full 100% exclusion after five years. For shares issued on or before July 4, 2025, the original rule applies — shares must be held for at least five years to receive any exclusion.

The clock starts when the corporation issues the shares — not when a secondary purchase was made, and not when options were granted. If shares are exercised from options, the holding period starts on the exercise date when stock is actually issued.

One exception: if you exchange qualifying QSBS for other QSBS in a tax-free reorganization within 60 days under §1045, the holding period can carry over. This is uncommon but worth knowing if a rollover deal is on the table.

The gross assets test

At the time of the original stock issuance, the C-corp must have had $75 million or less in gross assets (for shares issued after July 4, 2025 per Pub. L. 119-21) — or $50 million or less for shares issued before that date — including the proceeds from that issuance itself. Gross assets means cash plus the fair market value of contributed property. Not revenue. Not profit.

This matters most for companies that have raised significant outside capital. The cap table and historical financials — not current size — determine whether any given issuance qualifies. Shares issued in a financing round that pushed gross assets above the applicable threshold would not qualify even if earlier shares do.

The active business requirement

The corporation must be engaged in a qualified trade or business under §1202(e)(3) at the time of stock issuance and for substantially all of the holding period. Congress defined this specifically: some industries qualify, others are explicitly excluded.

The disqualifying industries share a common thread: they are businesses where the principal asset is the reputation or skill of individual employees. Note that “software” is qualifying even if the product is sold to enterprise clients as a professional tool. “Consulting” is disqualifying even if the firm also licenses software.

The original issuance requirement

Shares must be acquired directly from the corporation at original issuance — not purchased from another shareholder on a secondary market. This requirement applies to:

• Founders receiving shares at formation
• Employees exercising options and receiving stock issued by the corporation
• Investors participating in primary financing rounds

It does not apply to shares acquired from a selling shareholder, secondary transactions, or shares transferred or gifted (with limited exceptions for certain transfers to family members).

The exclusion cap: $15M / 15× (or $10M / 10× for older shares)

The exclusion is calculated on a per-taxpayer basis. For shares issued after July 4, 2025, the cap is up to $15 million of gain, or 15 times the investor’s adjusted basis in the stock, whichever is greater (Pub. L. 119-21). For shares issued before that date, the cap is $10 million (or 10× basis). Each investor in the same company gets their own exclusion — a company with ten qualifying early investors can generate over $150M in total excluded gain across all of them (for post-July 4, 2025 issuances).

Married couples filing jointly do not automatically double the exclusion limit. The exclusion applies to whoever’s name the shares were issued in. If both spouses received shares at original issuance, each gets their own exclusion. Trusts and partnerships that hold QSBS have more complex flow-through rules — consult counsel.

California non-conformity

Retroactive eligibility check

If you hold C-corp stock and have never checked §1202 eligibility, the analysis starts with six questions:

1. Was the entity classified as a C-corp at the time your shares were issued?
2. Did you acquire the shares directly from the corporation at original issuance?
3. Was the issuance date after August 10, 1993?
4. Did the corporation have $50M or less in gross assets at the time of your issuance (or $75M or less if shares were issued after July 4, 2025 per Pub. L. 119-21)?
5. Is the business in a qualifying trade or business under §1202(e)(3)?
6. Have you (or will you) hold the shares for at least three years from issuance? (Three years qualifies for a 50% exclusion, four years for 75%, and five or more years for the full 100% exclusion — for shares issued after July 4, 2025. Pre-BBB shares require five years for any exclusion.)

The answers require pulling the corporation’s cap table, historical financials at the time of issuance, and confirming the business activity classification with counsel. The check itself is not complicated — but the consequences of getting it wrong in either direction are significant.