A founder vesting schedule is the agreement that turns stock you already hold into stock you have actually earned, released over time instead of all at once. The market standard is four years with a one-year cliff: nothing vests for the first twelve months, then twenty-five percent vests in a single step, and the rest vests in monthly slices over the remaining three years. Founders tend to treat this as investor-imposed paperwork. It is closer to insurance, and the party it most often protects is the founder who stays.
The reason is arithmetic. Two founders split a company evenly, one leaves after five months, and without vesting that departing founder keeps half of everything the remaining founder spends the next eight years building. Investors call this dead equity, and they price it. It is the single most common reason a seed round stalls on diligence rather than on the product.
What a founder vesting schedule actually does
Most founder stock is not granted gradually. It is issued in full at incorporation and then made subject to a repurchase right: if the founder leaves early, the company can buy back the unvested portion, usually at the original purchase price, which is typically close to nothing. This is why the mechanism is often called reverse vesting. The founder owns the shares from day one, votes them, and starts the capital-gains clock, but the company holds a shrinking claw-back right that expires as the schedule runs.
That distinction matters more than it sounds. Because the shares are genuinely issued, the tax treatment, the voting rights, and the holding period all begin immediately. It also means the paperwork has to be right at the start, because you cannot retroactively make stock restricted once it is unrestricted without creating a taxable event.
The one-year cliff, and what it does on a bad day
The cliff is the twelve-month period during which nothing vests at all. Leave at month eleven and you keep nothing. Stay to month twelve and a full quarter vests at once. It exists to filter for commitment through the hardest stretch of company building, and it works, but it produces the sharpest edge in the whole document.
Two practical consequences follow. First, the cliff date deserves to be stated plainly in writing to everyone it applies to, because people routinely assume they are accruing something in months one through eleven and are genuinely shocked when they are not. Second, the start date is a real negotiation, not a formality. Vesting should generally run from the date the founder actually started working on the company, which is often months before incorporation. Founders who let the clock start at the first priced round donate their earliest and hardest year.
Vesting is usually described as protection for investors. In practice it protects the founder who stays, from the founder who does not.
Acceleration: the two triggers worth understanding
Acceleration decides what happens to unvested stock when the company is acquired. Single-trigger acceleration vests some or all of the remaining stock on the acquisition itself. Double-trigger acceleration requires two events: the acquisition, and then the founder being terminated without cause or resigning for good reason within a defined window afterward, commonly twelve months.
Double trigger is the market norm for founders and senior hires, and there is a reason acquirers prefer it. An acquirer is buying a team as much as a product. Full single-trigger acceleration hands everyone their stock at closing and removes the incentive to stay, which reduces what the acquirer will pay or forces them to fund a retention pool out of the purchase price. Double trigger protects the founder against being bought and then discarded, without repricing the deal. Asking for full single trigger across the founding team is one of the few equity requests that can visibly cost you money at exit.
The mistakes that cost the most
Four recur. Issuing founder stock with no vesting at all, which is fixable but awkward, since imposing vesting later means renegotiating with someone who currently owns unrestricted stock and has no reason to agree. Letting documents disagree, where an offer letter says four-year vesting and the stock purchase agreement says something else, in which case the signed agreement usually governs and the founder's expectation does not. Missing the 83(b) election, which must be filed within thirty days of the grant of restricted stock and which, if missed, can convert a trivial tax bill into a large one spread across every vesting date. And forgetting that vesting is only one half of the equity conversation, the other half being how the split was decided in the first place.
What to settle before the first round
Vesting is cheapest to get right at incorporation, when nobody has leverage and nobody is angry. Settle five things: the schedule length and cliff, the start date tied to actual work rather than incorporation, whether acceleration is single or double trigger and at what percentage, what counts as termination for cause and as good reason, and whether the same terms apply to every founder. Then make the stock purchase agreement, the board consent, and any offer letters say the same thing. Employee grants raise a parallel set of questions covered in ISO versus NSO stock options, and the whole package sits inside the broader startup legal documents checklist.
- The standard founder vesting schedule is four years with a one-year cliff: nothing for twelve months, then twenty-five percent at once, then monthly.
- Founder stock is usually issued in full and subject to a company repurchase right that shrinks over time, which is why it is called reverse vesting.
- Start the vesting clock from when work actually began, not from incorporation or the first priced round.
- Double-trigger acceleration is the market norm and protects a founder without repricing an acquisition; full single trigger can cost real money at exit.
- File the 83(b) election within thirty days of a restricted stock grant, and make every document state identical terms.
- No vesting at all is the version investors treat as a diligence problem, because a departing founder keeps everything.
A vesting schedule is not a statement of distrust between founders. It is the mechanism that makes an equity split survive contact with reality, including the version of reality where somebody leaves. Set it deliberately at the start, write it down consistently, and it will never need to be discussed again.
Related reading: how to split startup equity, the 83(b) election deadline, and ISO versus NSO options. Or start a conversation about getting founder equity documented cleanly.
Common questions
What is a founder vesting schedule?
A founder vesting schedule is the agreement that makes founder stock earned over time rather than owned outright from day one. The market standard is four years with a one-year cliff: no stock vests during the first twelve months, twenty-five percent vests at the twelve-month mark, and the balance vests in monthly increments over the remaining thirty-six months. Most founder stock is issued in full at the start and made subject to a company repurchase right over the unvested portion, so the founder holds and votes the shares while the company keeps a claw-back right that shrinks as the schedule runs.
What does a one-year cliff mean?
The cliff is a twelve-month waiting period at the front of the schedule during which nothing vests. A founder who leaves at month eleven keeps no stock; a founder who reaches month twelve vests twenty-five percent in a single step and then continues vesting monthly. The cliff exists to filter for commitment through the hardest early stretch of company building. Because the edge is sharp, the cliff date should be stated explicitly in writing to everyone it applies to, since people commonly assume they are accruing equity during those first eleven months.
When should founder vesting start?
Generally from the date the founder actually began working on the company, which is often before incorporation, rather than from the incorporation date or the first priced round. Founders who let the clock start at a later milestone give away credit for the earliest and usually hardest period of the work. The start date is a genuine negotiation point, and it should be recorded consistently in the stock purchase agreement, the board consent, and any offer letter, because inconsistent documents are typically resolved in favor of the signed agreement.
What is the difference between single-trigger and double-trigger acceleration?
Single-trigger acceleration vests unvested stock upon a single event, usually an acquisition. Double-trigger acceleration requires two events: the acquisition, and then a termination without cause or a resignation for good reason within a defined window afterward, commonly twelve months. Double trigger is the market norm for founders because it protects against being acquired and then dismissed, while preserving the retention incentive an acquirer is paying for. Broad single-trigger acceleration can reduce what an acquirer is willing to pay or force a retention pool out of the purchase price.