What Is Dilution?
Dilution is the reduction in ownership percentage that existing shareholders experience when a company issues new shares. Every funding round creates new shares, which means the pie gets bigger while each existing slice shrinks. It is not a tax and it is not a punishment, it is the mechanical price of bringing in capital, and it applies to founders, employees, and early investors alike.
Understanding dilution matters because percentages, not share counts, determine your share of the exit. If you hold 10,000 shares out of 100,000 you own 10%; if the company later issues 900,000 more shares for a Series A, your stake falls to 1% unless you participate. The conversation that matters is not "how many shares do I have" but "what percentage of the company will I own at the exit, and will that percentage be worth enough."
Where the Dilution Comes From
- Priced rounds: each new investor buys newly issued shares, diluting everyone who held shares before.
- Convertible instruments: notes and SAFEs convert into shares at the next round, adding to the dilution at conversion.
- Option pool top-ups: fresh equity reserved for employee grants, usually expanded at each round and frequently charged against founders.
- Anti-dilution and ratchets: protections that can re-price earlier investors' positions in a down round, shifting dilution onto founders and later investors.
Why It Matters to Investors
For investors, dilution determines whether a winning company produces a winning fund. A 10% stake diluted to 4% by Series C still pays well if the exit is large, but the math only works if the company's value grows faster than your ownership shrinks. That is why experienced angels ask about the full projected round path, not just today's valuation, and why they model "diluted ownership at exit" before writing a check.
Dilution and Deal Timing
The same capital raise produces very different dilution depending on when it happens. Raising at peak momentum means better valuations, and therefore smaller slices given away for the same dollars. GitDealFlow tracks the engineering signals (commit velocity, contributor growth, repository expansion) that typically accelerate 21-47 days before a fundraise becomes public, giving investors a window to act before momentum is priced in.
Frequently Asked Questions
How much dilution per round?
Seed: 15-25%. Series A: 20-30%. Series B: 15-25%. Series C+: 10-20%. Total dilution from founding to IPO: founders typically retain 5-15%.
Can I avoid dilution?
No. Growth requires capital. But you can optimize timing, raise when your engineering momentum (per GitDealFlow) is peaking for the best terms and least dilution.
Does the option pool dilute investors?
Yes. Pool top-ups dilute everyone, but the terms often specify whether the pool is carved out of the pre-money (founder cost) or added on top (shared cost). Always read which side the pool sits on.
What is a pre-money vs post-money option pool?
With a pre-money pool, the pool is created before the round, so founders absorb the dilution. With a post-money pool, it is created from new shares, spreading dilution across all shareholders including the new investor.