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Operator guideOption pool decisions are dilution decisions. Investors typically require expansion before their round; the timing affects whose ownership absorbs the dilution.
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Option Pool Sizing Guide · File.Business

Option pool sizing. How much to reserve.

Option pool size matters: too small and you cannot hire; too large and founders are over-diluted. Standard at incorporation: 10-15% of fully-diluted shares. At each funding round, investors typically require pool top-ups before their investment, which dilutes existing shareholders. This guide covers sizing strategies.

Key facts

Start here.

Key fact
Initial pool

10-15% of fully-diluted shares at incorporation.

Key fact
Pre-money expansion

At priced round, investors often require pool top-up to a defined size before their investment.

Key fact
Dilution mechanics

Pre-money pool top-up dilutes existing shareholders; post-money top-up dilutes all including new investors.

Key fact
Hiring plan informs size

Pool size should support next 18-24 months of hiring.

Key fact
Refresh periodically

Most companies refresh pool every funding round.

In depth

The full picture.

01

Initial pool at incorporation

Typically 10-15% of fully-diluted shares. Founders typically allocate this before or just after incorporation. Sized to cover anticipated grants over the next 18-24 months.

02

Pre-money pool top-up at fundraising

Almost all priced equity rounds include a pre-money option pool top-up: investors require the pool be expanded BEFORE their investment closes, so the dilution comes out of existing shareholders' equity rather than the new investors'. Standard ask: top-up to 15-20% of post-investment fully-diluted shares.

03

Dilution math

Example: pre-money $8M, raise $2M, pool top-up from 10% to 15% in pre-money. Existing shareholders dilute proportionally to the top-up. Founders pre: 80% (after 10% pool, 10% reserved). After top-up to 15% pre-money: founders dilute to ~76%. Then Series A 20% post-money dilutes to ~61%. Then post-money pool may be added.

04

Sizing the next pool

Estimate hiring plan over next 18-24 months. Standard equity grants: VP-level 0.5-1%, Director 0.25-0.5%, Senior IC 0.1-0.25%, Mid IC 0.05-0.15%, Advisors 0.1-0.25%. Sum projected grants; that is your target pool size.

05

Common mistakes

Pool too small at incorporation (you run out before next round). Underestimating hiring at later rounds (forced to expand mid-round). Letting investors choose pool size (they will push for larger pre-money expansion).

06

Refresh cadence

Most companies refresh pool at each priced round. Some refresh in between as needed via board action + shareholder approval.

07

Re-up grants

Many companies provide "re-up" grants to high performers as initial grants vest. Plan for this in pool sizing.

08

Exercise window post-termination

Standard 90-day exercise window. Some plans extend to 10+ years for ISO conversion to NSO. Plan provisions affect retention.

FAQ

Common questions.

What is an option pool?
An option pool is a block of equity a company reserves to grant as stock options to future employees, advisors, and other hires, so it can attract talent with equity without diluting founders unexpectedly later. It sits on the cap table as reserved shares. We keep your cap table organized so the pool is tracked accurately.
How big should my option pool be?
It depends on your hiring plans, commonly a meaningful percentage of equity set aside to cover expected grants until the next round, since too small forces awkward top-ups and too large over-dilutes founders. We flag how to size it against your hiring plan so the pool fits what you will actually grant.
How does the option pool affect founder dilution?
The pool comes out of ownership, so a larger pool dilutes founders more, and investors often require the pool to be created before their money goes in, increasing founder dilution. We flag how pool sizing and timing affect your ownership so you negotiate it with eyes open.
When is the option pool created?
Often before or at a financing, since investors typically want the pool established pre-money, which shifts its dilution onto founders, so the timing has real ownership effects. We flag how the pool's timing interacts with a round so its impact on your ownership is understood before you agree.
How are options granted from the pool?
Options are granted to hires with a strike price, usually set by a 409A valuation, and a vesting schedule, and each grant reduces the pool's remaining shares. We keep the pool and grants organized so you always know how much is left to grant.
What happens if the pool runs out?
If you exhaust the pool before your next round, you must either increase it, diluting existing holders, or you cannot grant more options, which can stall hiring. We flag the pool's remaining capacity so you top it up deliberately rather than discovering you are out mid-hire.
How does the pool relate to the cap table?
The option pool is a key line on the fully diluted cap table, showing reserved but ungranted equity, so tracking granted versus remaining is central to accurate ownership. We keep the pool and cap table aligned so your ownership picture stays accurate.
Do all startups need an option pool?
Startups that plan to hire with equity, most venture-track companies, generally establish one, while a business not granting equity may not need it, so it follows your hiring and funding plans. We flag whether and how large a pool fits your situation so you create it deliberately.
Can File.Business help me manage my option pool?
We form the corporation, set up the cap table, and keep the option pool, grants, and vesting organized, flagging how sizing and timing affect dilution, so your pool supports hiring without surprising you or your investors.

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