A founder’s stake falls from 70 percent to the mid-teens because dilution compounds: each round sells a share of the whole company, and the cuts multiply instead of adding. Three rounds that each hand 40 percent of the company to new investors and the option pool leave a 70 percent founder at 70 times 0.6 times 0.6 times 0.6, which is about 15 percent.
Key Takeaways
- Dilution compounds. Each round’s percentage applies to what you hold after the last round, so the cuts multiply.
- Your ownership after several rounds equals your starting stake times the retained fraction from each round. Model it as multiplication, not subtraction.
- Carta data put median dilution near 20 percent at seed and about 18 percent at Series A, so a light path leaves more than a heavy one.
- By Carta’s numbers, median founder ownership sits near 56 percent after a seed round and about 36 percent after Series A.
- Model three to four rounds before you sign the first term sheet. Set a floor, such as staying above 20 percent after Series B, and negotiate to it.
Dilution is the drop in your ownership percentage when a company issues new shares, most often to raise capital. It matters because your percentage, not your share count, decides your economic upside and your control, and each financing round lowers that percentage even when the company’s value climbs.
Why Does Dilution Compound Across Rounds?
Dilution compounds because each round issues fresh shares against a base that already grew in the last round. A cap table tracks every holder’s percentage. When new shares enter, the total share count rises and every existing percentage falls. The next round then cuts the already-reduced number again, so the effect stacks.
Model it as multiplication. Your ownership after several rounds equals your starting percentage times the fraction you keep in each round. Sell 20 percent of the company in a round and you keep 80 percent of what you held. Do that three times from 70 percent and you land at 70 times 0.8 times 0.8 times 0.8, which is about 36 percent. The number falls faster than subtraction would suggest, and that gap is what catches founders off guard.
How Can a 70 Percent Stake Reach the Mid-Teens?
Heavier rounds and stacked option pools get you there. Take a labeled scenario: three rounds that each transfer 40 percent of the company to new investors and refreshed option pools. The founder keeps 60 percent of their stake each time, so 70 times 0.6 times 0.6 times 0.6 lands at about 15 percent. Each step looks routine on its own. The compounding hides the total until the last round exposes it.
The lighter path shows the range. At Carta’s median dilution near 20 percent a round, three rounds from 70 percent leave about 36 percent, not 15. What pushes a founder into the mid-teens is a mix of larger rounds, an extra round, and option-pool expansions that dilute founders ahead of each raise. The lesson holds either way: run the multiplication before you agree to terms, because the drop compounds out of view.
Why Does a Higher Valuation Not Protect Your Ownership?
A higher valuation lowers the number of shares an investor gets for a given check, but it does not stop dilution. If you raise the same dollars at a higher price, you issue fewer shares, so the per-round cut shrinks. Raise more dollars because the valuation let you, and the cut grows again. The dollars you sell, set against the post-money value, drive the dilution, not the headline valuation.
Founders celebrate a valuation markup and miss the ownership math underneath. A $15 million round at a $60 million pre-money price sells 20 percent of the company. The same $15 million at a $30 million pre-money price sells 33 percent. The valuation changes the percentage you give up, so read every term sheet for the percentage sold, not the valuation alone.
Why Do Founders Miss Downstream Dilution?
They model one round and stop. Many founders calculate dilution for the raise in front of them and never project how the next two rounds interact with a growing cap table. Generic templates and non-specialist advisors often compute a single stage and assume later rounds mirror it. The company’s attention sits on the current raise and product, so the multi-round model waits, and the cost shows up later.
Assuming future rounds match the current one builds a blind spot. If the seed round cut 25 percent, a founder pencils in 25 percent for Series A and Series B. Later rounds can run higher or lower depending on the market, and an option-pool refresh adds dilution on top. Believing that a bigger, later-stage company keeps more equity on its own is the second trap: investors price a lower-risk company on their own terms, and the round can still take a large slice.
When Should You Model Dilution Before a Round?
Before you meet a single new investor. Build the model in the preparation phase, not after a term sheet arrives. Feed it your current ownership, the pre-money valuation you expect, and a dilution estimate for the next three rounds. With that projection you can see how much each percentage point of equity costs you downstream and set a floor you will not cross.
The floor turns the model into leverage. Decide, for example, to stay above 20 percent after Series B, and you can judge a term sheet against it on the spot. That lets you choose between raising more capital earlier to cut the number of rounds, or using instruments like a capped convertible that shift some dilution. Without the model, you react to investor pressure and lose ground you cannot recover.
How Do You Protect Ownership Across Multiple Rounds?
Buffer early and model the full path. Raising a larger seed to reach Series A on one round, instead of two seed-like rounds, removes a full multiplier from the chain. Set a conservative pre-money valuation that leaves room for the next raise, and plan for three to four rounds before an exit at a realistic dilution per round. Then run the multiplication so the cumulative number is a decision, not a surprise.
Non-dilutive and structured options extend the runway on ownership. Revenue-based financing can fund a growth phase without issuing shares. A convertible with a price cap or discount can shift some of the dilution a straight priced round would impose. Benchmark every term sheet against your ownership floor and decline the ones that push you under it. The founder who models early treats fundraising as ownership design, not a scramble for cash.
Frequently Asked Questions
How do you calculate ownership after several funding rounds?
Multiply your starting percentage by the fraction you keep in each round. If you sell 20 percent of the company in a round, you keep 80 percent of your prior stake, so the multiplier is 0.8. From 70 percent, three rounds at 20 percent give 70 times 0.8 times 0.8 times 0.8, or about 36 percent. Use multiplication, since dilution compounds rather than adds.
What is a typical dilution per round?
Carta’s data show median dilution near 20 percent at seed and about 18 percent at Series A, with Series B lower in recent quarters. Your round can land above or below the median depending on how much you raise and the market. Option-pool expansions add dilution on top of the headline round.
Does a higher valuation reduce dilution?
Only if you hold the raise amount steady. A higher pre-money valuation means fewer shares issued per dollar, so a fixed check dilutes you less. Raise more dollars because the valuation allows it and the dilution rises again. Read the percentage of the company sold, not the valuation headline.
When should a founder model dilution?
Before engaging any new investor, during preparation for the round. The model should include current ownership, the expected pre-money valuation, and dilution estimates for the next three rounds. That lets a founder set an ownership floor and test each term sheet against it.
How can founders reduce dilution across rounds?
Raise a larger early round to cut the number of rounds, set conservative valuations that leave room for the next raise, and consider non-dilutive or capped-convertible structures for some phases. Benchmark every term sheet against a stated ownership floor and decline terms that breach it. Modeling the full path early is the core discipline.
How ACG Models Ownership for Founders
Asea Capital Group builds the multi-round dilution model before a founder opens a raise. In a first round of $500,000 to $5,000,000, we project ownership across the next three to four rounds, set a floor with the founder, and structure the current raise to defend it. The founder walks into negotiations with the cumulative math in hand, so each percentage point sold is a choice rather than a surprise.
Prepared by Asea Capital Group, a capital-formation consulting firm in Miami, Florida. This article is educational and is not investment, legal, or tax advice. ACG is not a broker-dealer or law firm.
Sources: Carta, Founder Ownership Report; Carta, State of Private Markets, dilution data.
