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Exit Planning June 7, 2026

QSBS §1202: How Founders Exclude Up to $10M of Gain Tax-Free

The 5-year rule, the C-corp origin test, the SSTB trap, and the stacking strategies that multiply the cap. The structure has to be right from day one or the exclusion is gone.

TL;DR

IRC §1202 lets eligible founders and early shareholders exclude up to $10 million (or 10x basis, whichever is greater) of capital gain on the sale of qualified small business stock (QSBS), held for at least five years, originally issued by a C-corporation with under $50 million of gross assets at issuance. The stock has to be issued by a C-corp (not an LLC or S-corp converted later), the company has to use 80% or more of its assets in an active qualified trade or business that is not a specified service trade or business (SSTB), and you have to hold for five years. Done right, a single founder sells $10M of qualifying stock at zero federal capital gains tax. With stacking across family members, irrevocable trusts, and properly structured related entities, that $10M cap multiplies. The exit-time savings on the catalog row run from $1 million on the low end to $10 million on a clean stack. The reason most CPAs miss this: they surface it at exit, which is too late. The structure has to be right from day one.

What Qualified Small Business Stock actually is

Section 1202 has been on the books since 1993, was made permanent in 2015, and quietly became one of the most powerful tax provisions in the code once the §199A pass-through deduction made the C-corp form competitive again post-TCJA. For a founder taking outside capital and aiming at a venture-style exit, the exclusion is often the single largest tax planning lever available.

To be QSBS, the stock must clear five tests:

  1. C-corp from origin. The stock must be originally issued by a domestic C-corp. An LLC that converts to a C-corp later has stock from the conversion date forward; the basis brought in from the LLC era does not count, and any pre-conversion equity holders need a clean issuance event.
  2. Gross assets under $50 million. At the time of issuance and immediately after, the corporation must have aggregate gross assets of $50 million or less (measured at adjusted basis, not fair market value). Crossing the threshold permanently disqualifies any future issuances, but stock issued before the crossing remains QSBS-eligible.
  3. 80% active business use. During substantially all of the holding period, at least 80% of the corporation's assets must be used in the active conduct of one or more qualified trades or businesses.
  4. Not an SSTB or other excluded trade. Specified service trades and businesses (health, law, engineering for some interpretations, accounting, actuarial science, performing arts, consulting, athletics, financial services, brokerage services) are excluded. So are most banking, insurance, financing, leasing, investing, farming, mineral extraction, and hospitality businesses.
  5. Held by the original holder for 5+ years. Acquired at original issuance (not on the secondary market), held for at least five years before sale.

Every test is a pass-fail gate. Failing any one disqualifies the exclusion. Diligencing all five is the structuring work that has to happen at formation and at every issuance event after.

What the exclusion is actually worth

The cap is the greater of $10 million or 10 times the aggregate adjusted basis of the QSBS that the taxpayer disposed of in the year. For an early founder whose basis is rounding error (the $1,000 paid for the founder's stock), the binding cap is $10 million. For a later investor who paid $2 million for stock, the binding cap is $20 million.

At a 23.8% effective federal rate on long-term capital gains plus net investment income tax, $10 million of excluded gain is roughly $2.4 million of saved federal tax. State treatment varies: most states conform to federal §1202 (so the exclusion flows through), but a handful (California most notably) do not, so state tax still applies.

The Signal catalog scores the typical QSBS opportunity at $1 million to $10 million of one-time federal tax recovery, depending on the size of the gain and how well the stack was set up.

Stacking: how the $10M cap becomes $30M or $50M

The §1202 cap is per-taxpayer, per-issuer. Multiple taxpayers holding QSBS in the same company each get their own $10M (or 10x basis) cap. This is the basis for stacking strategies.

The common stack components:

  • Spouse. A founder gifts QSBS to a spouse before sale. Both spouses now have their own $10M cap on their respective stock. If filed jointly, the $10M caps are not combined (each spouse is a separate taxpayer for §1202 purposes).
  • Non-grantor trusts for children. A founder gifts QSBS into separate non-grantor trusts for each child. Each trust is its own taxpayer with its own $10M cap. Five children, five trusts, $50 million of additional excluded gain capacity beyond the founder's own cap.
  • Family members. Adult children, parents, siblings receiving gifted QSBS each have their own cap.
  • Tiered trusts. Multiple non-grantor trusts for the same beneficiary can each hold their own QSBS allocation, with the cap applying per-trust as long as the trusts are not aggregated under §643 attribution rules.

The stack has to be structured before the sale event, ideally years before. Gifting QSBS into a trust the week before a sale invites IRS scrutiny under step-transaction and assignment-of-income doctrines. Gifting at the formation stage or during a clean operational year, with proper appraisal and trust administration, is the defensible posture.

How to spot it on your own situation

For founders before a sale: pull your cap table, your formation documents, and your most recent corporate balance sheet. Walk through:

  • Is the company a C-corp? (If LLC or S-corp, the answer is no, but a conversion may still preserve future-issued stock.)
  • Was the company under $50M gross assets at the date your stock was issued? (Check the balance sheet for that quarter.)
  • Have you held the stock for five years? (Check your stock certificate or cap-table issuance date.)
  • Is the business an active trade or business, not an SSTB? (Software, manufacturing, biotech, consumer brands, agtech are the cleanest fits. Professional services usually fail.)

For founders after a sale that has already happened: pull Form 8949 from the year of sale. Look for the disposition row and check the column for the §1202 exclusion code (column (f) on Form 8949 should show code "Q" for qualified small business stock). If the row is missing the code, the exclusion was not claimed, and the question becomes whether it could have been (and, if so, whether you can amend within the statute of limitations).

Detection signal in the catalog: Form 8949 disposition without §1202 exclusion check-box; 1040 Schedule D missing the §1202 line.

Common mistakes that disqualify QSBS

  1. Started as an LLC, converted to a C-corp later. The pre-conversion equity is not QSBS. The post-conversion issuance can be QSBS if the conversion was structured cleanly and the gross-assets threshold is satisfied on the date of conversion-issuance.
  2. SSTB classification. The single most common disqualifier in practice. A "tech-enabled services" company that is really a consulting business with a software wrapper fails the SSTB test. A law firm with a software product, a healthcare staffing company, a wealth-management platform: probably SSTB.
  3. Gross-assets threshold crossed. The $50M test is measured at issuance and immediately after. A growth-stage company that grew through a Series B round and crossed $50M of gross assets has any stock issued after the crossing disqualified; stock issued before is still QSBS-eligible if every other test holds.
  4. Failed 80% active-business test. A company sitting on a large cash position relative to operating assets (think a company that raised $100M and is burning $1M/quarter, with $97M of working capital sitting in T-bills) can fail the 80% active-use test, since cash and investments do not count toward active business use unless they are reasonably required for working capital.
  5. Sold before five years. A four-year-and-eleven-month sale fails the 5-year rule. There is a §1045 rollover provision that lets a holder who is short of the 5-year hold reinvest the proceeds into other QSBS and tack on the holding period, but it requires speed (60 days from sale to reinvestment) and care.
  6. Stacking transactions too close to sale. Gifting QSBS to a trust the month before a signed LOI invites the IRS to challenge under step-transaction or assignment-of-income. The cleaner the timeline between the gift and the sale, the cleaner the position.

When generalist CPAs miss it (and why "missing at exit" is the canonical failure)

The canonical §1202 failure mode: the CPA hears about QSBS for the first time the week the LOI is signed, when there is no longer time to clean up the structure. The 5-year clock cannot be retroactively started. The C-corp origin cannot be retroactively imposed on an LLC-formed entity. The stack cannot be defensibly built in the month before a sale.

The work has to start at formation. Choose C-corp. Document the $50M gross-assets test at every issuance. Document the active-business and non-SSTB posture annually. Build the basis schedule. Identify the family members and trust structures that would receive gifted QSBS years before the sale.

Generalist CPAs miss §1202 for three reasons:

  1. The structuring work happens before the company is profitable, before there is a CPA on the engagement at all. The work belongs to the founder's startup attorney, who often does not run the §1202 analysis.
  2. The annual documentation work (gross-assets snapshots, SSTB analysis, active-business analysis) is housekeeping that does not bill at a premium rate. It tends to slip.
  3. The exit-side analysis is specialized. A generalist preparing the return in the year of sale will often code the disposition straight as a long-term capital gain without checking whether the §1202 box could have been ticked.

The Signal diagnostic surfaces this either way: for founders pre-exit, the structuring conversation; for founders post-exit, the amendment analysis if the exclusion was missed on the original filing.

Related reading

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