What it means
A share option gives you the right to buy company shares at a fixed price, called the strike or exercise price, which is usually set at the share value on the day the option was granted. Exercising means actually paying that price and receiving the shares.
Normally you can only exercise options that have vested, meaning you have served enough time to earn them. Some companies offer an early exercise provision that lets you buy unvested shares immediately, with the company keeping the right to buy them back at your cost if you leave before the shares would have vested.
The appeal is tax and timing. In most systems, the gap between the strike price and the market value on the day you exercise is a taxable amount, so exercising when that gap is tiny keeps the immediate tax bill small and puts any later increase into the capital gains category, which is normally taxed more lightly than salary.
The cost is that you are now an investor rather than an option holder. The cash is gone, the shares are usually illiquid, and if the company fails you lose both the money you paid and the tax you may already have handed over.
Anyone exercising early on unvested shares generally needs to file a specific election with the tax authority within a strict window, commonly 30 days, to be taxed on today's low value rather than on the value when the shares vest. Missing that filing window is the single most expensive administrative error in this whole area.
Early exercise is best suited to people joining very early, when strike prices are pennies and the total cheque is small relative to their savings. It suits people much less well after several funding rounds, when the same decision can mean writing a six-figure cheque for something with no market.
In practice
Real-world examples.
Example
A designer joins a two-person startup as employee number four and exercises all 30,000 of her options in month one, when the strike price is $0.05, for a total of $1,500. She files the required tax election within 30 days and treats the money as gone.
Example
A senior engineer at a company three funding rounds in looks at early exercising 60,000 options at a $4.00 strike, a cost of $240,000, and decides against it because that is most of his savings and the shares cannot be sold.
Example
A departing operations manager has 90 days after leaving to exercise vested options or forfeit them. She exercises only the tranche she can comfortably afford, accepting that she is letting the rest lapse rather than borrowing against an uncertain outcome.
Formula
Calculation
Cash cost to exercise = Number of options x Strike price
Paper spread at exercise = (Fair market value per share - Strike price) x Number of options
An early employee holds 40,000 options with a strike price of $0.25. The company's latest independent valuation puts the fair market value at $0.40 per share, and the plan allows early exercise of unvested options.
Cash cost = 40,000 x $0.25 = $10,000.
Value of shares received = 40,000 x $0.40 = $16,000.
Paper spread = ($0.40 - $0.25) x 40,000 = $0.15 x 40,000 = $6,000.
The employee pays $10,000 in cash and reports a $6,000 spread, which is small enough to be manageable. If the company is later acquired at $9.00 per share, the shares are worth 40,000 x $9.00 = $360,000, giving a gain of $360,000 - $10,000 = $350,000 measured from the exercise cost.Case study
Seen in the real world.
Consider Wexler Instruments, an illustrative and entirely fictional maker of laboratory sensors. Its first ten employees were granted options at a $0.10 strike and offered early exercise, and the finance lead ran a short session explaining both the tax election and the risk that the money would simply disappear.
Six of the ten exercised, spending between $800 and $4,000 each. Four decided the cash mattered more than the potential upside and kept their options unexercised, which was a perfectly reasonable decision given their circumstances.
Four years later Wexler was acquired. The six who had exercised early were taxed largely at capital gains rates on their proceeds, while those who exercised only at the point of sale saw a much larger slice treated as employment income. The illustrative lesson is not that early exercise is always right, but that the decision has to be made when the numbers are small, because by the time the outcome is obvious the option to choose has gone.
Watch out
Common mistakes.
- Assuming early exercise is free money. It converts cash you already have into shares that may become worthless, and no tax advantage rescues a company that fails.
- Missing the short filing window for the tax election on unvested shares, which can leave you taxed on the much higher value at each vesting date instead of today's low value.
- Confusing exercising with selling. Exercising only means you now own private shares, and in most cases you cannot turn them into cash until an acquisition, a buyback or a formal secondary sale.
Questions
People also ask.
Does every company allow early exercise?
No, it is a specific plan feature, and many companies leave it out because tracking repurchase rights over unvested shares adds administrative work.
What happens to early exercised shares if I leave?
The company typically buys back the still-unvested shares at the price you originally paid, so you get your cash back on those but keep the shares that had vested.
Is early exercise sensible for late joiners?
Usually much less so, because the strike price has risen with each funding round, which makes the cheque large and the downside far more painful.
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