Evaluating Pre-IPO Equity in a Job Offer: The Real Expected-Value Math

The offer is 45,000 options at a $6 strike, a $240,000 base, and a $50,000 sign-on. The recruiter tells you the company’s last Series C priced at $22 per share and the current 409A is $9. They hint at a $4 billion post-money and a “path to IPO” in 18 to 30 months. You multiply: 45,000 × ($22 - $6) = $720,000. That is not what this package is worth. It is a headline number that ignores dilution, preference, vesting probability, and the wide distribution of possible exit outcomes.

Most public “offer calculators” produce this headline number. Most employees then anchor on it during salary negotiation. Knowing the real probability-weighted expected value of the equity makes you a better negotiator (because you can trade a lower headline for a higher base) and prepares you for the realistic spread of outcomes.

This guide walks through the inputs, the framework, and two worked examples that bracket the realistic range.

The inputs you need

Five categories of inputs drive the math. Get as many as you can from the recruiter and HR before accepting.

Equity grant specifics

Share count
Strike price
Grant date (affects 409A reference)
Vesting schedule (including cliff and acceleration terms)
Whether grants are ISO or NSO
Exercise window after termination (standard 90 days, extended 7-10 years at some companies)

Company valuation markers

Current 409A per share
Most recent preferred price per share
Total fully-diluted shares outstanding
Total preference stack

Expected rounds and dilution

Stage of company (Series B, C, D, etc.)
Announced or expected time to liquidity
Typical dilution per round at the company’s stage

Exit scenario distribution

Probability of IPO vs acquisition vs bust
Range of exit valuations in each scenario

Your own variables

Expected tenure (how many years of vesting you actually collect)
Your marginal tax rate
Your opportunity cost (what the outside-option compensation pays)

The expected-value framework

Expected value = Sum across all scenarios of (probability × net-after-tax proceeds to your shares in that scenario).

A simplified four-scenario model covers most late-stage situations:

Scenario	Probability	Exit value	Common-stock outcome
Bust	15%	$0 or below stack	$0 to common
Mild	25%	Near last valuation	Low residual after preference
Successful IPO or large acquisition	45%	2-4x last valuation	Strong pro-rata
Home run	15%	5-10x last valuation	Very strong pro-rata

These weights are approximate; adjust to your read of the company. An AI company at Series C with strong hiring and growth might merit 25% home run and 5% bust. A slowing late-stage company might flip the weights.

For each scenario:

Project fully-diluted share count at exit (current + expected dilution).
Calculate proceeds per common share at the exit value.
Subtract strike to get net gain per share.
Multiply by your expected vested share count (not headline share count).
Subtract taxes (ordinary for NSOs, long-term cap gains for ISOs held properly).

Worked example: Series C AI company

Offer: 45,000 options at $6 strike, 4-year vest, 1-year cliff, ISOs. Current 409A $9, last preferred $22. 200 million fully-diluted shares. $900 million preference stack. Expected 36 months to liquidity.

Expected vested shares if you stay the full four years: 45,000. Realistic tenure at a Series C: many employees leave at 2.5-3 years. Expected vested count: 28,000 (62% of grant).

Dilution from here to IPO: one Series D (-15%), one pool refresh (-5%), IPO issuance (-8%). Post-dilution: 0.72x of current ownership.

Expected fully-diluted shares at IPO: 200M × (1/0.72) = 278M (because dilution from your perspective is a reduction in your denominator’s inverse).

Scenario math

Bust (15%): $500M exit. Preferred takes all. Net: $0.

Mild (25%): $4B exit. Preferred converts (above stack breakeven). Proceeds to common pool: $4B × 40% = $1.6B. Per share: $1.6B / 278M = $5.76. This is below the $6 strike. Net: $0 (options underwater).

Successful (45%): $12B exit. Preferred converts. Proceeds to common: $12B × 40% = $4.8B. Per share: $17.27. Net per share before tax: $11.27. Your shares (28,000): $315,556. After long-term cap gains at 32.8% federal (23.8%) + 13.3% CA: $212,259. Note: ISO requires 2+1 holding for LTCG treatment.

Home run (15%): $30B exit. Per share: $43.17. Net per share: $37.17. Your shares: $1,040,760 gross. After tax: $700,031.

Expected value

0.15 × $0 + 0.25 × $0 + 0.45 × $212,259 + 0.15 × $700,031 = $200,521

That is the expected after-tax value of the equity package. Over four years, that is ~$50,000/year in equity expected value. Compare to the next-best offer at higher base but no equity to decide whether the equity is worth taking a lower salary.

Worked example: Series B biotech

Offer: 20,000 options at $3 strike. 409A $4, last preferred $12. 150M fully-diluted. $180M preference. Expected 48+ months to liquidity.

Expected vested: 14,000 (70% at 4 years given biotech often has longer tenure).

Dilution to IPO: two priced rounds plus pool refresh plus IPO. Post-dilution: 0.55x.

Scenarios

Bust (35%, higher for biotech): $0.

Mild (25%): $600M exit. Preferred converts. Common pool: $600M × 35% = $210M. Per share: $0.85. Underwater. Net: $0.

Successful (30%): $3B exit. Common pool: $1.05B. Per share: $4.24. Net per share: $1.24. Your 14,000: $17,360. After tax: $11,666.

Home run (10%): $10B. Per share: $14.14. Net: $11.14. Your 14,000: $155,960. After tax: $104,795.

EV = 0 × 0.6 + 0.3 × $11,666 + 0.10 × $104,795 = $13,979

Over four years, $3,495/year. The biotech equity at Series B has much lower expected value than the Series C AI example despite higher headline share count ratio, because the bust and mild scenarios consume most of the probability.

How to use the math in negotiation

If the recruiter quotes a headline equity value of $720,000 on an offer where your expected value is $200,000, you have leverage. Two moves:

Trade equity for base

Ask for a $20,000 base increase in exchange for reducing equity by some amount. If the company agrees, you captured certain dollars today rather than probabilistic dollars in 3-5 years.

Trade equity structure

Some companies will swap options for RSUs (with delayed settlement) or offer early-exercise privilege. Early exercise of ISOs starts the QSBS 5-year clock and the LTCG holding period at exercise rather than at vest (see the ISO exercise article).

Demand the cap-table numbers

A company that shares fully-diluted share count, preference stack, and current 409A is signaling transparency. A company that refuses is hiding something. Willingness to share data correlates with respect for employee equity outcomes.

Common traps

The single most common mistake. 409A times share count is not the option’s expected value. The expected value is always lower once you factor dilution, preference, vesting probability, and exit distribution.

Assuming 4x vest collection

Unless you are deeply committed to staying for the full vest period, assume 50-70% of vested shares. Most employees leave before full vest, triggering forfeiture of unvested shares.

Ignoring taxes

A gross equity outcome of $1 million at a 50% effective rate is $500,000 after tax. Tax matters, especially for NSOs (ordinary income on spread) and ISOs that fail the 2+1 holding rule.

Overweighting the home-run scenario

Every startup pitch sells you the home-run. The probability-weighted math forces you to consider the bust and mild scenarios, which tend to dominate the distribution.

Frequently asked

What about refresher grants?

Most late-stage companies offer annual refresher grants at 15-40% of the initial grant size. If you expect refreshers, add them with discounting. A $30k refresher this year plus a smaller one next year, plus further dilution, adds meaningfully to EV at long tenure.

Should I early-exercise?

Early-exercise converts options to common stock at the strike price, triggering tax on the spread at exercise. For ISOs, the spread is an AMT preference item. For QSBS purposes, exercising early starts the 5-year clock sooner. Worth evaluating if you believe in the company’s growth and have cash to cover the exercise and potential AMT.

What does “path to IPO” actually mean?

It is a recruiting phrase. Some companies have filed S-1, engaged underwriters, and have a clear timeline. Most have not. Ask specifically: “Have you engaged IPO counsel? Have you filed confidential S-1? What is the target window?”

How do I value double-trigger RSUs?

Similar framework but no strike price. Net proceeds per share = settlement price. Settlement price approximates exit value × common-ownership fraction of fully-diluted shares, discounted to present.

Does acceleration-on-change-of-control help?

Single-trigger acceleration (100% vest on CoC) is rare and usually reserved for C-suite. Double-trigger acceleration (vests on CoC + termination within a window) is more common. Acceleration helps in acquisition scenarios but does not change IPO-scenario math.

Next step

Before your next negotiation call, pull these inputs for the offer: share count, strike, vesting schedule, current 409A, last preferred price, rough fully-diluted count, and any public preference-stack information. Run the four-scenario model with your own probability weights. That gives you an expected-value number. Negotiate with that number in mind, not the headline.