Option Pool

The block of equity reserved for employee stock options at a startup — its size affects how much dilution founders and early employees experience, and understanding it is essential for evaluating startup equity offers.

An option pool (also called an employee equity pool or employee stock option pool) is a set of company shares reserved specifically for granting to employees, advisors, and contractors as equity compensation. Option pools are created when a company incorporates or when it raises funding — venture investors often require companies to set aside a pool before a financing round closes, typically 10–20% of the post-financing capitalization. The pool is composed of authorized but unissued shares that haven't yet been granted to anyone; they exist as reserved capacity for future grants. As the company makes equity grants to employees, the pool shrinks; when it's depleted, the board must approve an increase (which requires creating new shares and causes dilution to all existing shareholders).

For employees receiving equity offers, the option pool matters for two reasons. First, the size and replenishment philosophy of the pool affects whether there will be ongoing equity to grant — if a company is rapidly hiring and depleting its pool, early employees may find that refreshes and new grants slow down or stop unless the board approves an increase. Second, and more subtly, how the pool is sized relative to the cap table affects valuations and dilution in ways that aren't always transparent in offer letters. Investors often require that the option pool be created before a round closes (pre-money), which means the dilution of creating the pool falls on the existing shareholders (founders and early employees) rather than the new investors. A 20% pre-money option pool at a $10M pre-money valuation means founders are diluted by the pool before the investors calculate their ownership percentage.

For employees evaluating startup equity offers, the key questions about the option pool are: what percentage of the fully diluted capitalization does the pool represent, and how does this compare to the industry norm (15–20% at most early-stage companies)? If the pool is very small, early equity grants may be disproportionately large as a percentage of the pool, but the company may run out of room to make future grants to new hires. If the pool is large, grants tend to be smaller as a percentage of the pool. The absolute number of shares matters less than the percentage of fully diluted shares — asking for your grant as a percentage of total fully diluted shares is the most useful way to compare equity offers across companies at different stages and valuations.

How the Option Pool Affects Your Equity

  • Size matters for dilution: a large pre-money pool dilutes existing shareholders (founders and early employees) before investors come in. This is why investors push for large pools — the dilution lands on existing shareholders, not them.
  • Percentage vs. shares: always ask what percentage of fully diluted shares your grant represents, not just the number of shares. The number of shares means nothing without knowing the total outstanding.
  • Pool refresh: when a pool is depleted, the company must authorize new shares — this dilutes all existing shareholders including employees with vested equity. Frequent refreshes at growing companies are normal.
  • Pool utilization rate: ask how much of the pool is already committed. A company with a 15% option pool and 14% already granted has almost no room for new grants without dilutive expansion.
  • Post-money vs. pre-money pool: a pre-money option pool (required by investors before funding) creates dilution that falls on existing shareholders. A post-money pool creates dilution that investors share. Pre-money pools are the standard; know which you're looking at.
  • 409A valuation: the fair market value of common shares for option pricing (strike price) is determined by a 409A valuation, an independent appraisal typically done annually or after each financing. The strike price is set at 409A value at time of grant.

Questions to Ask About Equity at a Startup

When evaluating equity at a startup, the offer letter will typically state a number of shares. That number alone is nearly meaningless without context. The questions that actually matter are: What is the total fully diluted share count? (Makes the percentage calculable.) What is the 409A valuation (FMV of common stock)? (Determines your strike price.) What was the price per share in the most recent financing round? (Provides a reference point for preferred share price.) What percentage of the option pool has been granted? (Signals how many more grants the company can make before needing a dilutive expansion.) What are the most recent company valuation and revenue metrics? (Contextualizes the equity upside.) Has the company previously done a 409A refresh, and when is the next one? (Affects whether your strike price will be higher if you join after the next appraisal.) Founders and HR at early-stage companies are accustomed to these questions and should be able to answer them — if they can't or won't, that's important information.

Example

A startup with 10 million fully diluted shares offers a software engineer 100,000 options. The 409A valuation is $3/share (strike price), and the most recent Series A priced preferred stock at $8/share. The engineer's grant is 1% of fully diluted shares. If the company exits at $50/share, her 100,000 options are worth ($50 − $3) × 100,000 = $4.7 million before taxes. If the company exits at $4/share (below the Series A preferred price, triggering liquidation preference considerations), her upside may be significantly less than that calculation suggests. Understanding the liquidation preference stack — how preferred investors get paid before common shareholders — is essential context for evaluating that $4.7M number.