A company promises a key employee a piece of the upside. Not real shares, nothing so formal, just an understanding written into an offer letter: when we sell, you get a share of the proceeds. Everyone means it kindly. Years later the sale closes, the reward is paid, and it arrives with a tax bill no one planned for and a federal penalty on top, charged not to the company that made the promise but to the employee it was meant to reward.
That outcome has a name, and it is one of the most quietly dangerous provisions in the tax code for private companies: Section 409A. The trouble is that the promises most likely to trigger it are the ones made most casually, in the language of encouragement rather than the language of contracts. This is 409A in plain English: what it is, why "equity someday" so often falls inside it, and how to make the same promise without the penalty.
What §409A actually is
Section 409A governs nonqualified deferred compensation, which is a technical phrase for a simple idea: pay that is earned in one year and paid in a later one. Congress wrote the rule after a wave of executive-pay scandals, and it wrote it strictly. If an arrangement counts as deferred compensation and does not follow the rules, the tax consequences are severe and they are early.
Current as of July 2026. When a 409A arrangement is out of compliance, the recipient is taxed as soon as the pay is vested, meaning no longer subject to a real risk of forfeiture, even if not a dollar has actually been paid yet. On top of that early ordinary income tax comes an additional 20% federal tax, plus an interest charge. Read that again, because it is the part that surprises everyone: the penalty falls on the executive or employee, the person you were trying to reward, not on the company that drafted the promise. A 409A failure is a drafting mistake whose bill is handed to the one person who had no say in the drafting.
Why "equity someday" is usually 409A territory
Owners rarely think of an equity promise as deferred compensation, but the tax code often does. The forms that catch companies by surprise are the ones that feel least like formal comp:
- Phantom equity. A contractual right to a future cash payment measured by the value of the company or its growth. It gives a key person the economics of ownership without issuing real shares, which is often exactly right for a closely held company. It is also deferred compensation, squarely inside 409A.
- Transaction and exit bonuses. The classic "you will get a share when we sell." A payment tied to a future event is deferred compensation, and if the event and its timing are not defined the way the rules require, the promise is noncompliant from the day it is made.
- Discounted options. Options priced below fair market value at grant are a 409A problem. Options priced at or above fair market value on the company's stock are generally exempt, which is why a defensible valuation matters and why a casual strike price is a risk.
- Deferred and delayed bonuses. Bonuses paid well after they are earned can slip into 409A unless they are structured to fit an exemption.
The common thread is that none of these announce themselves as "deferred compensation" to the person writing the offer letter. They announce themselves as generosity. The tax code is not moved by the framing.
What compliance actually requires
Compliance is a drafting discipline, not a filing. In plain terms, 409A insists that a deferred payment be nailed down in advance rather than left flexible:
- The payment trigger and timing must be fixed when the promise is made, and limited to the events the rules allow, such as a set date, a separation from service, death, disability, or a change in control. "We will pay you when it feels right" is not a permitted trigger.
- You cannot freely speed the payment up or push it back once it is set. The flexibility owners assume they have is largely what the rule takes away.
- "Change in control" has to be defined to match the tax rule, not a looser business definition. This is the single most common failure in exit bonuses: the event that pays out is described in ordinary deal language that does not line up with what 409A requires.
- Any options or appreciation rights must be priced at fair market value, supported by a valuation the company can defend.
None of this is exotic once someone is looking for it. All of it is invisible if no one is.
The good news: design it right and the problem disappears
409A is not a reason to stop rewarding the people who build your company. It is a reason to design the reward before you promise it. Most arrangements can be made clean in one of two ways.
The first is to fit an exemption. The most useful one lets pay escape 409A entirely if it is paid promptly after it vests, within the short window the rules allow. A great many bonuses can be written to land inside that window, and then the rule simply does not apply. The second, for genuine deferred compensation like phantom equity, is to comply on purpose: lock the payment triggers and timing to what the rules permit, define the change in control correctly, and price any options at fair market value. Either path delivers the same economics you intended. The difference is that the recipient keeps the reward instead of paying a penalty for how it was written.
This is also why timing is everything. A 409A problem is inexpensive to prevent and frequently impossible to fix after the promise has been documented, because the correction rules are narrow and unforgiving. The design conference belongs before the offer letter, not after the dispute. And because the analysis is a tax analysis at heart, it is done in coordination with your tax advisor, so the legal structure and the tax treatment agree.
Before you promise the upside
If you have already promised someone "equity someday," or you are about to, the question worth asking is not whether the promise is generous. It is whether it is deferred compensation, and if it is, whether it complies or fits an exemption. That question is cheap to answer now and expensive to answer later, and the person most exposed to the wrong answer is the one you were trying to keep.
Design the incentive before the promise is made →
This material is for general information only and is not legal advice; reading it does not create an attorney-client relationship. It describes federal tax rules at the level of principle, current as of the date shown; those rules are detailed and fact-specific, and this is not tax advice. Design any deferred compensation with counsel and your tax advisor before it is promised.