Read the Cap Table, Not the Headline: What You Actually Own After Three Rounds

Every founder can quote their valuation. Almost none can tell you what they’ll own after the round after the next one. That gap is where fortunes quietly leak out.

The mistake is treating dilution as a single subtraction — “I sold 20%, so I keep 80%.” Dilution isn’t subtraction. It’s multiplication, compounded across every round, and bent by terms most founders never read: the SAFE cap that converts worse than they assumed, the option pool that comes out of their slice, the pro-rata rights that let existing investors keep buying while the founder gets squeezed.

Valuation is the number you brag about at the bar. Ownership is the number that shows up on your exit wire. They are not the same conversation, and the terms — not the headline price — decide which one you’re actually having.

Dilution is multiplication, not subtraction

Here’s the mental model that fixes most of the confusion. Each financing event multiplies your ownership by a retention factor — the fraction of the company that isn’t newly issued. Give up 20%, and you keep 80% of what you had. Do it three times and you don’t subtract 20% three times to get 40%. You multiply:

0.80 × 0.80 × 0.80 = 0.512. Three “20% rounds” leave you with just over half. Nobody sold you 60% of your company — but that’s what left.

And that’s the clean version, before the terms get involved. Two mechanics quietly make it worse, and both hide in the paperwork rather than the price:

1. The option pool shuffle. Investors almost always require a fresh option pool before the round closes — a “pre-money pool.” That means the dilution from the pool lands entirely on the existing shareholders (you), not the new investor. A 10% pool created pre-money isn’t shared; it’s yours to fund.
2. SAFEs that convert worse than the sticker. A SAFE with a valuation cap converts at the cap, not the priced round’s valuation. Stack two or three uncapped-looking SAFEs with different caps and discounts, and the effective ownership they claim at conversion can be far larger than the “we only gave away 8%” you remember agreeing to.

The clauses that actually move your number

• Valuation cap & discount (SAFEs/notes): the lower the cap, the more of the company that money buys when it converts. Two SAFEs at different caps dilute you unevenly.
• Pre- vs. post-money option pool: “10% pool” pre-money can cost you several extra points of ownership versus the same pool created post-money.
• Pro-rata / participation rights: lets existing investors buy their share of future rounds, keeping their ownership steady — which means yours keeps absorbing the difference.
• Liquidation preferences: a 1x non-participating pref behaves very differently from a 2x participating one at exit. Your percentage can look fine while your payout gets gutted in a modest sale.
• Anti-dilution (full ratchet vs. broad-based weighted average): the difference between a down round nicking you and a down round detonating your stake.

A worked example: from 100% to what, exactly?

Take two co-founders who split the company 50/50 and raise three times. Watch the terms, not just the headline percentages.

The founders started at 100%, told themselves they’d “given up 20% at seed and 22% at A,” and expected to hold something like 58%. They hold roughly 46% between them — about 23% each — before the next round. The missing twelve points weren’t in any headline number. They were in the pre-money pool and the SAFE conversion. That’s the entire game.

Common mistakes founders make

• Reading the cap as the price. A $5M cap on a $500K SAFE isn’t “we gave up 10%.” It’s “we gave up whatever 10% grows into by the time it converts against a real round.”
• Ignoring who funds the option pool. Agreeing to a pool “for hiring” without noticing it’s pre-money, and therefore entirely on your ledger.
• Optimizing valuation over terms. Taking the higher cap with a 2x participating pref instead of the lower cap with clean 1x non-participating — and losing more at a realistic exit.
• Modeling one round at a time. Each round looks survivable in isolation. The compounding is only visible when you model all three at once.
• Treating the shareholders’ agreement as boilerplate. Drag-along, pro-rata, and consent rights shape control and future dilution as much as the numbers do.

The problem: doing this well by hand is genuinely hard

Modeling dilution correctly means holding several moving parts in your head at once — SAFE caps and discounts converting at different valuations, pre- versus post-money pool timing, pro-rata top-ups, and the interaction between them across rounds. A spreadsheet can do it, but building one that handles SAFE conversion mechanics correctly is its own small project, and one wrong cell propagates silently through every downstream round.

So most founders skip it. They read the SAFE once, nod at the cap, sign, and discover the real math two years later when a term sheet forces them to actually build the cap table. By then the terms are set. The clauses that quietly cost the most — pre-money pools, participation, ratchets — are exactly the ones that read like legal filler if you don’t already know what they do.

The fix: read every clause before you sign it

Alchemy breaks down SAFEs, term sheets and shareholder agreements clause-by-clause, so you understand your dilution before you sign — not after. Instead of skimming a document you’re not trained to read, you get each clause explained for what it actually does to your ownership: how the valuation cap converts, whether the option pool lands pre- or post-money, what the liquidation preference and anti-dilution language mean when a real exit or a down round arrives.

It’s the difference between signing on trust and signing on understanding. You still make the call — Alchemy makes sure you’re making it with the clauses in plain sight.

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It’s not the only way

Understanding your dilution has several legitimate paths. Here’s an honest read, including where Alchemy falls short.

The bottom line

Dilution compounds, and the terms — not the valuation — decide how hard. Three “reasonable” rounds can leave founders with under half the company, and most of the damage hides in clauses that read like boilerplate: pre-money pools, SAFE caps, participation, ratchets. You don’t need to become a securities lawyer. You do need to understand every clause before you sign it, because after you sign, the math is no longer yours to argue with.

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