Section 1202 of the Internal Revenue Code is, for founders and early-stage investors, often the largest single tax benefit available in the United States. Held correctly for the requisite period, qualified small business stock (QSBS) lets a non-corporate holder exclude capital gain on the sale of that stock up to a per-issuer-per-shareholder cap. For a successful exit, the math frequently runs into eight figures of saved federal tax. The mechanics, though, are exacting, and the recurring losses observed in venture-formation practice often trace to a structural decision made years before the gain was ever realized.
Post-OBBBA framework. The One Big Beautiful Bill Act (Pub. L. 119-21, July 4, 2025) substantially restructured Section 1202. For QSBS acquired after the applicable date in 2025, the per-issuer-per-shareholder dollar cap is $15 million (subject to inflation adjustments beginning in 2027), the gross-asset cap on the issuer is $75 million under Section 1202(d), and the holding period is tiered: a 50% exclusion at three years, 75% at four years, and 100% at five or more years. For QSBS acquired on or before the applicable date, the legacy framework continues to apply: $10 million per-issuer cap, $50 million gross-asset cap, and a single five-year holding period. Founders and investors holding pre-OBBBA stock should evaluate which framework governs each block of stock with a qualified tax advisor; the analysis is fact-specific and turns on the issuance date.
This insight walks through the operative requirements of Section 1202, the related rollover provision in Section 1045, and the planning points that come up most often in venture-formation engagements.
The Core Exclusion
Under 26 U.S.C. § 1202(a), a taxpayer other than a corporation may exclude from gross income a percentage of the gain from the sale or exchange of qualified small business stock held for more than five years. For QSBS acquired after September 27, 2010 and on or before July 4, 2025, the exclusion is 100 percent of the eligible gain after a five-year hold, subject to the per-issuer-per-shareholder cap. For stock acquired after July 4, 2025, the post-OBBBA tiered framework controls (50% at three years, 75% at four years, 100% at five years).
The cap, set out in 26 U.S.C. § 1202(b)(1), is the greater of:
- $10 million for stock acquired on or before July 4, 2025, or $15 million for stock acquired after July 4, 2025 (post-OBBBA, with inflation indexing beginning 2027), reduced by the aggregate amount of eligible gain taken into account in prior taxable years on dispositions of QSBS issued by the same corporation, or
- 10 times the aggregate adjusted bases of QSBS issued by the corporation and disposed of by the taxpayer during the taxable year.
For a founder who acquired stock at par for very low basis, the $10 million prong is what controls. For a sponsor or institutional investor who put real money in, the 10x basis prong can produce a much larger exclusion. The taxpayer takes the greater of the two on a per-issuer basis.
For QSBS acquired after September 27, 2010 (the cutoff under 26 U.S.C. § 1202(a)(4), enacted by the Small Business Jobs Act of 2010, Pub. L. 111-240 § 2011, and made permanent by the PATH Act of 2015, Pub. L. 114-113 § 126), the excluded gain is not an alternative minimum tax preference and is exempt from the 3.8 percent net investment income tax under Section 1411. The 7 percent AMT preference under former § 57(a)(7) continues to apply only to the excluded portion of gain on QSBS acquired on or before September 27, 2010 (a narrow population of pre-2010 founder stock and similar vintages). For all post-9/27/2010 QSBS, the headline 100 percent exclusion is the after-tax percentage; there is no quiet AMT clawback to rebuild the exposure. The corporate alternative minimum tax under Section 55, as added by the Inflation Reduction Act, Pub. L. 117-169 § 10101, applies only to corporations with average annual adjusted financial statement income above $1 billion and does not affect the holder-level Section 1202 analysis at any company that meets the Section 1202(d) gross-asset cap.
Issuer-Level Requirements
Stock qualifies as QSBS only if the issuer meets a structural test that runs both at issuance and substantially throughout the taxpayer's holding period.
Domestic C-corporation
Under 26 U.S.C. § 1202(c)(1), the issuer must be a domestic C-corporation. LLCs taxed as partnerships, S-corporations, and most foreign entities cannot issue QSBS. A common path is to form as an LLC for early operating flexibility and convert to a C-corporation later, but the conversion has consequences for the QSBS holding period: the stock issued at conversion is treated as issued at conversion (not at LLC formation), so the five-year clock starts fresh. Where preserving QSBS treatment matters, forming as a C-corporation at the outset is materially simpler than retrofitting it.
Gross-asset cap (Section 1202(d))
Under 26 U.S.C. § 1202(d)(1), the issuer must have aggregate gross assets at or below the statutory cap at all times before and immediately after the issuance. The cap is $50 million for stock acquired on or before the OBBBA applicable date in 2025 and $75 million for stock acquired after the applicable date. "Gross assets" means cash plus the adjusted bases of other property, with contributed property valued at fair market value rather than the basis the property had in the contributor's hands. The cap is on assets, not on enterprise value: a company with $30 million of paid-in capital and a $1 billion enterprise value still passes if the cash and other assets are within the applicable cap.
The cap is measured at every issuance. Once the company first crosses the applicable cap in gross assets, stock issued after that point is no longer QSBS, but stock that was QSBS at issuance does not lose its status because the company later grows past the cap.
Active-business requirement
Under 26 U.S.C. § 1202(e), during substantially all of the taxpayer's holding period, the issuer must use at least 80 percent of its assets by value in the active conduct of one or more qualified trades or businesses. Working capital and assets held for two years or less in connection with reasonably anticipated research, R&D, or business needs count toward the 80 percent.
The principal trap here is investments. A company that accumulates significant cash and parks it in marketable securities for an extended period can fail the active-business test as the cash exceeds two-year working-capital reasonableness. Late-stage companies with large balance sheets sometimes lose QSBS status not because the operating business changed but because the treasury function did.
Excluded businesses
Under 26 U.S.C. § 1202(e)(3), certain businesses are categorically excluded:
- Any trade or business involving the performance of services in health, law, engineering, architecture, accounting, actuarial science, performing arts, consulting, athletics, financial services, brokerage services, or any trade or business where the principal asset is the reputation or skill of one or more employees.
- Banking, insurance, financing, leasing, investing, or similar business.
- Farming (including raising or harvesting trees).
- Any business involving the production or extraction of products of a character with respect to which a deduction is allowable under Sections 613 or 613A (oil, gas, coal, certain minerals).
- Hotel, motel, restaurant, or similar business.
The "consulting" prong has produced the most litigation and the most uncertainty, particularly for software-as-a-service businesses that include implementation or customer-success components. The IRS and Tax Court have generally focused on whether the principal value of the business is in deliverable software/IP versus in advice or services. Founders in adjacent categories (fintech with broker-dealer affiliates, marketplace businesses with insurance components) need a deliberate Section 1202 analysis at formation.
Holder-Level Requirements
To claim the exclusion, the taxpayer must be a non-corporate holder, must have acquired the stock at original issuance (directly or through an underwriter), and must hold it for more than five years.
Original issuance
Under 26 U.S.C. § 1202(c)(1)(B), the stock must have been acquired by the taxpayer at its original issue, in exchange for money, other property (not including stock), or as compensation for services provided to the issuer. Stock purchased on a secondary market does not qualify, with limited exceptions (stock received by gift or inheritance can tack on the donor's holding period and QSBS character; stock received in a Section 351 contribution or a tax-free reorganization may have special treatment under Section 1202(h)).
Holding period
Under Section 1202(a), the stock must be held for more than five years. The clock starts on the date of issuance. For a founder who issued and filed an 83(b) election on January 15, 2026, the earliest QSBS-eligible sale is January 16, 2031. There is no concept of an averaging or weighted-average holding period; each tranche is measured separately.
Section 1045 Rollover
The most-overlooked provision in early-stage tax planning is 26 U.S.C. § 1045. Section 1045 allows a non-corporate taxpayer who has held QSBS for more than six months but less than five years to elect to defer the gain by rolling the proceeds into replacement QSBS within 60 days of the sale.
The mechanics:
- The taxpayer sells QSBS held more than six months. The gain is otherwise immediately taxable because the five-year period is not yet met.
- Within 60 days of the sale, the taxpayer reinvests an amount equal to or greater than the proceeds in replacement QSBS issued by a different qualifying issuer.
- The taxpayer files an election under Section 1045 with the return for the year of sale.
- The gain is deferred to the replacement stock. The taxpayer's holding period in the original stock tacks onto the replacement stock for purposes of meeting Section 1202's five-year requirement.
For founders sitting on a year-four acquisition offer, Section 1045 is the answer to the question, "do I have to take the full tax hit if I sell now?" Provided the proceeds can be redeployed into another QSBS-eligible company within 60 days, the answer is no. The replacement stock then runs to its own five-year mark, with the prior holding period tacked on, and the eventual qualifying sale produces the same Section 1202 exclusion that would have been available on a year-five-plus sale of the original stock.
Section 1244 as the Downside Counterpart
The often-missed companion to Section 1202 is 26 U.S.C. § 1244, which lets a non-corporate holder of stock in a domestic small business corporation treat up to $50,000 ($100,000 on a joint return), per taxable year, of loss on the stock as ordinary loss rather than capital loss. Because ordinary losses can be deducted against ordinary income at much higher marginal rates than capital losses can be used, the asymmetry is meaningful: capital gain on a successful exit (Section 1202), ordinary loss on a failure (Section 1244).
Section 1244 has no formal-plan filing requirement following the 1978 amendment (P.L. 95-600); stock qualifies if the corporation meets the "small business corporation" definition in IRC § 1244(c)(3), which requires that aggregate capital not exceed $1,000,000 at the time the stock is issued. Most venture-backed companies will outgrow that ceiling at the first priced round; founders therefore typically lose Section 1244 eligibility on stock issued after the seed stage. Where the limit is not yet exceeded, recordkeeping at formation that documents the stock as Section 1244 stock costs essentially nothing and preserves the ordinary-loss option for the early-issued shares.
Where Founders Most Often Go Wrong
Five recurring losses we see in venture-formation engagements:
- Forming as an LLC and converting to a C-corporation at financing. The conversion restarts the five-year clock for the stock issued at conversion. A founder who operated as an LLC for 18 months and converts at the seed round is now sitting in year zero of a five-year QSBS clock, not year 1.5. Where QSBS treatment matters, formation as a C-corporation from the outset is the right call.
- Operating in a Section 1202(e)(3) excluded line of business. Most common in fintech (financial services / brokerage), consulting-heavy SaaS (consulting), and crypto exchange businesses (financial services / brokerage). A deliberate analysis at formation is the difference between a $10 million federal-tax-free exit and a $10 million federal-tax-burdened exit on the same dollar.
- Crossing the gross-asset cap before key issuances. The Section 1202(d)(1) cap (legacy $50 million; post-OBBBA $75 million) is measured at issuance, on aggregate gross assets. Stock issued after the company first crosses the applicable cap is not QSBS, even if the stock issued before the cap remains QSBS forever. Companies in the late-stage growth band sometimes issue secondary stock to employees that could have been QSBS, had it been issued earlier.
- Failing to file 83(b) on unvested founder stock. If the stock is subject to vesting and no Section 83(b) election is made within 30 days, the stock is not "issued" for QSBS purposes until it vests. The QSBS holding period therefore begins on the vesting date of each tranche, not on the original grant date. The fix is to file 83(b) timely, which both produces ordinary-income consequences at $0 (for stock issued at fair value) and starts the QSBS clock at issuance.
- Selling at year four without a Section 1045 rollover. A year-four sale that could have been a Section 1045-deferred rollover into replacement QSBS instead becomes a fully taxable gain. The 60-day reinvestment window is short, but the planning happens before the sale closes, not after.
Planning at Formation
QSBS is not a tax election made at sale. It is a structural condition that runs from formation through the eventual exit. The decisions that determine QSBS eligibility are made when the company is incorporated, when founder stock is issued, when 83(b) elections are filed (or missed), when the company first issues stock at scale, and at any point the active-business test could break.
For founders building toward an exit five-plus years out, the structural QSBS analysis at formation is the highest-expected-value tax planning available. The same analysis applies to angel and seed investors, who have their own per-issuer cap (the greater of $10 million in cumulative gain or 10x adjusted basis under ยง 1202(b)(1), and as adjusted under the One Big Beautiful Bill Act for stock issued after July 4, 2025) and run their own holding-period clock.
For background on how QSBS planning fits into the broader formation architecture (entity choice, founder equity, IP assignment, financings, and governance), see our long-form guide on Setting Up a Venture: Formation, Capitalization, and Term Sheets.