---
title: "What Is Anti-Dilution?"
term: "Anti-Dilution"
description: "Anti-dilution protection adjusts an investor's conversion price if the company issues shares later at a lower price—protecting early preferred holders from down-round dilution beyond normal ownership math."
date: 2026-07-25T00:00:00.000Z
updated: 2026-07-25T00:00:00.000Z
topics: ["deal-terms"]
source: https://venturecapitaltracker.com/glossary/anti-dilution
---

# What Is Anti-Dilution?

> Anti-dilution protection adjusts an investor's conversion price if the company issues shares later at a lower price—protecting early preferred holders from down-round dilution beyond normal ownership math.

**Anti-dilution** is a preferred-stock provision that retroactively lowers an investor's effective purchase price when the company raises a qualifying down round, issuing them additional shares.

## How it works

Two common flavors: **broad-based weighted average** (standard, milder adjustment using a formula with old and new prices and shares outstanding) and **full ratchet** (harsh—reprices to the new low price as if the investor originally paid that). The charter specifies which financings trigger adjustment and carve-outs for employee options, strategic warrants, or conversions.

On a down round, lawyers model the cap table before and after anti-dilution to show founder and employee dilution. Some rounds negotiate waivers in exchange for other concessions.

## Why it matters

- **Founders:** Push for broad-based weighted average; avoid full ratchet unless crisis financing leaves no choice.
- **Investors:** Anti-dilution protects entry price; waiving it is a bargaining chip in recapitalizations.
- **Operators:** Option pool refresh after anti-dilution events may be needed to retain talent.

## Common mistake

Assuming anti-dilution only matters in bankruptcy scenarios. A moderate down round with full ratchet can transfer massive ownership from common to preferred.

## Related ideas

[1x liquidation preference](/glossary/one-x-liquidation-preference), down round, pay-to-play, and recapitalization.

## FAQ

### What is anti-dilution in simple terms?

If you sold Series A at $2 per share and later sell Series B at $1, anti-dilution gives Series A investors extra shares so their effective price moves toward the new lower price—depending on whether the clause is broad-based weighted average or full ratchet.

### Why does anti-dilution matter?

It determines who eats the pain in a down round. Founders and employees on common stock feel the squeeze when preferred anti-dilution triggers. Investors view it as standard downside protection.


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Source: https://venturecapitaltracker.com/glossary/anti-dilution