Deal Terms
Weighted Average Anti-Dilution
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Quick Answer
The most common form of anti-dilution protection, adjusting an investor's conversion price based on both the new lower price and the number of shares issued.
What it is
Weighted average anti-dilution is the standard form of anti-dilution protection in VC deals. When a company raises a down round, weighted average anti-dilution adjusts the conversion price of existing preferred stock based on: how many shares were sold at the lower price AND what that lower price is. The formula weighs the impact, meaning a small down round with few shares issued has a modest adjustment, while a large down round with many shares issued has a bigger adjustment. Broad-based weighted average (BWAM) includes all outstanding shares in the calculation — the most founder-friendly variant. Narrow-based weighted average includes only preferred shares, making the adjustment more aggressive. Both are more founder-friendly than full ratchet (which resets the conversion price to the new low price regardless of volume).
In Practice
Imagine Blockchain Ventures invested $2M in CryptoFlow at $8M pre-money, receiving 1M preferred shares at $2 per share. Later, CryptoFlow raises a down round at $1.50 per share, issuing 2M new shares. Using narrow-based weighted average, if there were 5M shares outstanding, the weighted average price becomes: (5M × $2 + 2M × $1.50) ÷ 7M = $1.86 per share. Blockchain Ventures' conversion price adjusts from $2.00 to $1.86, giving them additional shares upon conversion to maintain their economic position despite the down round.
Operational context
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Why It Matters
This protection prevents investors from being severely diluted in down rounds while being more founder-friendly than full ratchet provisions. For founders, understanding the math helps in negotiations — weighted average is generally acceptable since it provides reasonable investor protection without completely destroying founder ownership. For investors, it's essential protection that maintains economic incentives even when valuations decline, though the specific formula (broad vs narrow-based) significantly impacts the actual adjustment.
VC Beast Take
Most experienced VCs will push for narrow-based weighted average, which includes fewer shares in the calculation and provides stronger protection. Smart founders negotiate for broad-based, which dilutes the anti-dilution effect. The real trick is in the details — what counts as 'outstanding shares' can dramatically change the math. Don't just accept standard language without modeling different scenarios.
Term Family
Related concepts
Further Reading
VC Term Sheet Template & Guide: Every Clause Explained with Examples
A clause-by-clause breakdown of every standard VC term sheet provision — what each term means, what's market, what to negotiate, and the red flags that cost founders millions.
Share Dilution Explained: Formula, Examples, and How to Protect Your Equity
The dilution formula every founder needs to know, three worked examples from simple to multi-round, how option pools really work, and practical strategies to protect your ownership stake.
NVCA Model Legal Documents: Every Form a Startup Founder Needs
The NVCA publishes free legal templates that can save you $10-30K in lawyer fees. Here's every document explained in plain English, plus what to watch for.
Startup Valuation Calculator: How to Calculate Pre-Money and Post-Money Valuation
Pre-money valuation doesn't have to be a mystery. Here are the exact formulas, three worked examples at different stages, and the methods VCs actually use to price early-stage startups.
VC Interview Questions: 30 Questions They'll Actually Ask (With Answers)
30 real VC interview questions organized by category: technical, market thesis, deal evaluation, and behavioral. With frameworks for answering each one.
The Real Cost of Raising Venture Capital (Fees, Dilution, and Hidden Risks)
Most founders think raising $5M means getting $5M. It doesn't. Here's the real math on dilution, legal fees, time costs, and hidden terms that nobody warns you about.
Related Guides
How to Negotiate a VC Term Sheet: A Founder's Leverage Guide
A founder's guide to negotiating VC term sheets: leverage mechanics, which terms actually matter, specific tactics, and real scenarios with concrete playbooks.
How to Read a Term Sheet: Line-by-Line Guide for Founders
Every major term sheet clause decoded: liquidation preference, board composition, anti-dilution, vesting, protective provisions, and more. With a negotiation priority list at the end.
Understanding Startup Equity and Dilution: A Complete Guide
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Related Questions
What is a down round?
A down round is a funding round where a company raises capital at a lower valuation than its previous round. It dilutes existing shareholders and triggers anti-dilution provisions for preferred investors.
What is a term sheet?
A term sheet is a non-binding document that outlines the key terms of a proposed investment — valuation, amount, ownership percentage, and governance rights. It's the starting point for negotiating a deal.
What is anti-dilution protection in venture capital?
Anti-dilution protection adjusts an investor's share price downward if the company later raises money at a lower valuation, protecting the investor from being diluted by a down round.
Frequently Asked Questions
What is Weighted Average Anti-Dilution in venture capital?
Weighted average anti-dilution is the standard form of anti-dilution protection in VC deals. When a company raises a down round, weighted average anti-dilution adjusts the conversion price of existing preferred stock based on: how many shares were sold at the lower price AND what that lower price...
Why is Weighted Average Anti-Dilution important for startups?
Understanding Weighted Average Anti-Dilution is critical for founders navigating the fundraising process. It directly impacts deal terms, valuation, and the relationship between founders and investors.
What category does Weighted Average Anti-Dilution fall under in VC?
Weighted Average Anti-Dilution falls under the deal-terms category in venture capital. This area covers concepts related to the financial and legal terms that define investment agreements.
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