QSBS: The Startup Stock Tax Rule Founders, Employees, and Investors Shouldn’t Overlook.

A Tale of Two Investors

Picture two hypothetical early investors in the same software company. In March 2021 she wrote her check to the company in its seed round. A few months later he bought the same class of shares from a co-founder who wanted some cash. In August 2026 the company sold, and each walked away with $10 million of gain.

She owed nothing in federal tax on it. He owed about $2.38 million.

Same company, same stock, same closing day. The difference was who sold them the shares. QSBS follows only stock that comes straight from the company, and his came secondhand, so no amount of holding time or paperwork could fix it. (The pair is an illustration, but the rules and the math are real).

He paid a fair price. He just paid it to the wrong person.

What QSBS is, in Plain Terms

Qualified Small Business Stock (Section 1202 of the tax code, if you want to look it up) lets individuals, trusts, and estates that own stock in a qualifying young company leave a large slice of their gain out of federal taxable income when they sell. Not a deduction. An exclusion: the gain simply never gets taxed.

For stock acquired after July 4, 2025, the exclusion is the greater of $15 million or 10 times your tax basis (usually what you paid), per taxpayer, per company. Older stock gets $10 million or 10 times basis. A married couple filing jointly generally shares one cap. On a $15 million gain, a top-bracket family would otherwise owe about $3.57 million in federal tax.

Newer stock also earns partial exclusions at three and four years. Is the three-year tier half off? Closer to a third, because the half that stays taxable is taxed at a higher rate (up to 28% plus 3.8%). And no stock acquired under the new rules can reach even that tier before July 2028.

Five Gates, Every Share

Think of QSBS like provenance on a painting. The same canvas sells for a fortune with its paper trail and a fraction without one. QSBS is a paper trail for stock. Some gates are tested the day your shares are issued; the company tests have to keep holding for substantially all the years you own them. Miss one and that share is ordinary stock, no matter how well the others did.

Two gates surprise people most. Gate 2 is measured on the balance sheet (roughly, cash plus the tax basis of the company’s other assets), not the valuation. A company valued at $500 million can still qualify; one valued at $90 million right after an $80 million raise can fail, because the cash alone puts it over the ceiling. Gate 3 makes timing personal. The company may be ten years old; your shares may be two. Every option exercise and every RSU settlement is a new issuance with its own test, which is why a founder’s early shares often pass while an executive’s later grants in the same company don’t. Company buybacks matter here too: a repurchase from you or a relative within two years of your issuance, or a sizable one from anyone within a year, can disqualify the shares.

Gate 4’s excluded fields are broader than most people expect: health, law, engineering, architecture, accounting, actuarial science, consulting, performing arts, athletics, financial services, brokerage, banking, insurance, financing, leasing, investing, farming, oil, gas and mining, hotels and restaurants, and any business whose main asset is its employees’ reputation or skill. The quick screen: is the company selling something it built, or its people’s time?

Who’s Likely Holding It

• Founders: The first question we’d ask: Was the company a C corporation when your shares were issued, and can you prove your 83(b) was filed?
• Early employees and executives: The first question we’d ask: When did you exercise or settle each grant, and how big was the company’s balance sheet on those dates?
• Angels and direct investors: The first question we’d ask: Did you buy from the company itself, and what exactly did that SAFE or convertible note turn into?
• Fund and SPV investors: The first question we’d ask: Were you already in the fund on the day it bought the stock? Late joiners don’t share in the benefit.
• Heirs and gift recipients: The first question we’d ask: For gifts: the shares keep their status, so the giver’s records become yours. For inherited shares, the step-up in basis at death often matters more. We check both.

And for CPAs, attorneys, insurance professionals, and business managers: You don’t have to be the QSBS expert. You just have to spot the stock. Three questions do most of the work: Is it a C corporation? Did the shares come straight from the company? Is anyone talking about a sale? Two yeses and a maybe is worth a phone call.

What the Internet Gets Wrong

QSBS has become a favorite of finance social media, and the short version travels fast: invest under $75 million, hold five years, $15 million tax-free. That sentence skips most of the five gates. Each claim below has circulated in the last few years on posts, blogs, or firm websites with real audiences.

What you’ll hear: “Invest in a company valued under $75 million.” 
What’s actually true: The test is gross assets on the balance sheet, not valuation. And the shares must come from the company; buying from another shareholder never counts.

What you’ll hear: “Exclude $15 million on every qualified investment.” 
What’s actually true: The cap is per company, not per check: every later investment in the same company draws on the same cap, and prior QSBS gain from that company counts against it. $15 million applies only to stock acquired after July 4, 2025; older stock starts at $10 million.

What you’ll hear: “Nearly every venture-backed company qualifies.” 
What’s actually true: Plenty don’t: fintech and brokerage-style marketplaces, health services, consulting-heavy models, and companies whose later rounds pushed assets past the ceiling. In one published analysis, IRS lawyers treated an online rental marketplace as an excluded brokerage.

What you’ll hear: “Your C corporation can sell its property and exclude the gain.” 
What’s actually true: QSBS is a benefit for shareholders selling stock. In an asset sale the company pays corporate tax (21% federal) first; shareholders’ gain on the later payout may still qualify, but the corporate layer doesn’t go away.

What you’ll hear: “Ten trusts, $100 million tax-free, and you can borrow the money back.” 
What’s actually true: Only trusts that are truly separate taxpayers add a cap. Borrowing back or keeping access can make a trust count as you, and then it adds nothing.

What you’ll hear: “Restricted stock starts its clock at grant, even before vesting.” 
What’s actually true: Only with a timely 83(b) election, filed within 30 days. Without one, the clock starts at each vesting date, and each vesting can bring ordinary income.

The pattern: Almost none of these get the tax rate wrong. They get the tests wrong, because the tests don’t fit in a caption.

QSBS Stacking (Legitimate vs. Overly Aggressive)

The exclusion can be multiplied, legitimately. Because the cap is per taxpayer, a gift of shares to an adult child, or to a properly built trust that files as its own taxpayer (a “non-grantor” trust), gives that new owner a separate cap. The shares keep their QSBS status and holding period along the way. Planners call this stacking.

Let's consider this hypothetical example. Imagine a founder with three adult children, stock bought at original issue in 2018 for $300,000, and a $60 million gain expected in 2027. With no planning, she excludes $10 million and pays about $11.9 million in federal tax. With one well-built trust per child, funded early in 2026 before any banker was involved, the family excludes $40 million and the bill falls to about $4.76 million. That’s $7.14 million saved on the same sale. The gifts also used about $9 million of her lifetime gift-tax exemption, which makes this an estate-planning decision as much as a tax one.

The marketing runs past the law at predictable spots. A trust your spouse can benefit from (the familiar SLAT) usually counts as you for income tax, so it adds nothing. Look-alike trusts created together for the same beneficiaries can be treated as a single trust. If the IRS does that, most of the savings disappear, and penalties of 20% to 40% can apply on top. Treasury has noticed, too: in May 2026 a senior Treasury official warned a room of practitioners, in so many words, that Treasury doesn’t like stacking and that guidance is likely.

We don’t know yet exactly what that guidance will say, or how far back it can reach. We do know which structures tend to hold up best: the plain ones. One real trust per real beneficiary, funded early, with an independent trustee and a clean paper trail. And before asking how many trusts a plan can support, ask how much you need to keep for yourself. A gift that works for tax purposes is a gift: the money is no longer yours.

The Clock Nobody Watches

Smart, well-advised people lose this all the time, and not because the rules are secret. The reward is five years away and the paperwork is due now. Behavioral economists call it present bias: we discount effort whose payoff sits far in the future. The 83(b) form, the balance sheets from the year you invested, the trust signed before a buyer calls, all feel optional right up to the week they become impossible.

The fix is to treat the exit as a date you’re already counting down to, even if you don’t know it yet. These are planning milestones, not legal deadlines, but each stage narrows what can be done cleanly.

And federal tax-free doesn’t mean tax-free everywhere. States treat QSBS differently (some not at all, some only in part), and several changed their rules in 2026, in both directions. Residency, where the gain is sourced, and any trust’s connections to a state all factor in, and moving before a sale doesn’t automatically end your old state’s claim.

Let’s Look at It Together

Ask your Composition Wealth advisor for a QSBS review with our Wealth Strategy Group. If you’re a CPA, attorney, or other advisor, a short introduction is enough; we’ll work alongside you and share every finding. You don’t need a complete file to begin.

• Bring what you have:
• Bring what you have:
• Stock certificates, grant agreements, and option exercise records
• Any 83(b) elections, with proof of mailing
• The company’s cap table and any QSBS letter it has issued
• Trust documents and gift tax returns, if shares have changed hands
• Where you expect to live when you sell

We’ll hand back a share-by-share map: what appears to qualify, what still needs proof, the dates that matter, and what each open move could be worth in dollars.

Schedule your review before your next funding round, option exercise, gift, or banker conversation. Each of those can change the answer, and several of them can’t be undone.

New to Composition Wealth? Contact us for a consultation.

 

Important information. This primer is for general education only and is not tax, legal, or investment advice. The investor and founder examples are hypothetical; figures are illustrative, assume top-bracket 2026 federal rates (20% on long-term capital gain plus 3.8% net investment income tax, and 28% plus 3.8% on the taxable part of a partial exclusion), assume each company and share lot meets every requirement, and exclude state tax. QSBS eligibility depends on facts specific to each company, shareholder, and share lot, and tax laws and IRS guidance change. Consult your own tax and legal advisors before acting. Composition Wealth is a registered investment adviser; registration does not imply a certain level of skill or training.

Composition Wealth, LLC (“Composition Wealth”) is a registered investment adviser. Advisory services are offered only to clients or prospective clients where Composition Wealth and its representatives are properly licensed or exempt from licensure. This communication is for informational purposes only and should not be considered financial, tax, or legal advice. Please consult with your professional advisors before making any financial decisions.

Composition Wealth and its affiliates do not provide tax, legal or accounting advice. This material has been prepared for informational purposes only, and is not intended to provide, and should not be relied on for, tax, legal or accounting advice. You should consult your own tax, legal and accounting advisors before engaging in any transaction.