What does anti-dilution protection actually do?

Of all the terms in a term sheet, anti-dilution is the one founders are least likely to negotiate and most likely to regret. The reason is simple: it has no effect whatsoever unless you raise at a lower price than the last round, and at the moment of signing nobody plans to do that.

So it gets waved through as boilerplate. Then a difficult eighteen months happens, the next round comes in below the last one, and a clause nobody discussed decides how much of the damage lands on the founders rather than on the investors.

The difference between the two common versions of it, on ordinary numbers, is several points of founder ownership. It is worth twenty minutes.

What it is protecting against

An investor who paid ₹26 a share is unhappy if the company later sells shares at ₹15. Their money bought fewer shares than the same money buys now, and nothing they did caused that.

Anti-dilution protection addresses it by retrospectively improving their price. It does not give them cash back. It issues them additional shares, as though they had originally paid something closer to the new price, and those shares come out of everyone else's ownership.

That framing matters. A down round dilutes everyone. Anti-dilution decides how the dilution gets distributed, and it moves it away from the protected investors and onto whoever is not protected. In most companies that is the founders and the employee pool.

Anti-dilution does not reduce the damage of a down round. It decides who absorbs it.

The two versions, and why the gap is so large

Broad-based weighted average

This is the market standard and the one to push for. It adjusts the earlier investor's conversion price part of the way towards the new price, in proportion to how much cheap money came in relative to the size of the company.

The mechanism is a formula that your documents will set out, and the shape of it is: the new conversion price equals the old one, multiplied by the shares outstanding before the round plus the shares the new money would have bought at the old price, divided by the shares outstanding before the round plus the shares actually issued.

The important property is proportionality. A small down round moves the price very little. A large one moves it more. That is a reasonable answer to a real problem.

The word broad-based refers to what counts in the share count. A broad basis includes options and convertibles, which dilutes the adjustment and favours founders. A narrow basis counts only the preference shares, which makes the adjustment larger. If your documents say narrow-based, that is worth a conversation.

Full ratchet

A full ratchet ignores proportionality entirely. The earlier investor's entire holding is repriced at the new price, however small the new round is.

One share issued at ₹15 can reprice a ₹10 crore investment as though all of it had been made at ₹15. That is not a description of a risk being shared. It is a transfer, and its size has no relationship to the size of the event that triggered it.

Full ratchets appear in difficult markets and in bridge rounds where the investor has the stronger position. They are not unheard of and they are not standard, and a founder should know which one they have signed.

A worked example

Illustrative figures throughout, continuing a cap table where a Series A investor put in ₹10 crore at ₹26.4444 a share for 37,81,513 shares, with 1,89,07,563 shares outstanding fully diluted and the founders holding 52.89%.

Now the company raises ₹6 crore at ₹15 a share, which is 40,00,000 new shares. A real down round, and not a catastrophic one.

• ·With no anti-dilution at all, total shares become 2,29,07,563 and the founders fall from 52.89% to 43.65%. The down round itself costs them 9.24 points, and that part is unavoidable.
• ·With broad-based weighted average, the Series A conversion price moves from ₹26.4444 to ₹24.4461. They receive 3,09,124 extra shares, and the founders end at 43.07%. The protection costs the founders a further 0.58 points.
• ·With a full ratchet, the Series A conversion price drops all the way to ₹15. They receive 28,85,154 extra shares, and the founders end at 38.77%. The protection costs the founders a further 4.88 points.

The ratchet issues more than nine times as many extra shares as the weighted average does, off the same down round. Nine times.

Pay to play, and why it can help you

A pay-to-play provision says an investor only keeps their anti-dilution protection, and sometimes their preference terms, if they participate in the down round to their full pro-rata share.

Founders should generally want this. It aligns the protection with continued support: an investor who backs the company in a hard round keeps their downside cover, and one who declines converts to ordinary shares and loses it.

It also changes the dynamics of the round itself. Existing investors deciding whether to participate are choosing between putting money in and giving up protection, which tends to produce more money in the round and a cleaner cap table afterwards.

It is worth asking for at the original round, when it costs nothing and sounds reasonable, rather than trying to negotiate it during the down round when everyone's position has hardened.

What to actually ask for

1. 01Broad-based weighted average, not narrow-based and not a ratchet. This is the market standard and asking for it is unremarkable.
2. 02Pay to play, so protection follows support.
3. 03Carve-outs, so ordinary events do not trigger an adjustment: shares issued under the ESOP pool, shares issued on conversion of existing instruments, shares issued in a bona fide acquisition, and shares issued with the consent of the protected investors themselves.
4. 04A floor, if you can get it, so the conversion price cannot fall below some stated level.
5. 05Clarity on whether the adjustment is automatic or requires notice, because the mechanics matter when it is being applied under time pressure.
6. 06And a modelled answer, written down next to the term sheet, showing what each version would do at a plausible down round.

That last item is the one entirely within your control. You may not win the negotiation on the clause, and you will at least know what you agreed to.

Where the ESOP pool gets hurt

One consequence that catches companies out: anti-dilution shares dilute the option pool along with everyone else, and the pool is usually not topped back up.

So after a down round with meaningful anti-dilution adjustment, the pool is a smaller percentage of the company than the board intended, and the outstanding grants are worth less than the people holding them believed. At exactly the moment the company most needs to retain its team.

The practical response is to model the pool percentage after the adjustment and decide deliberately whether to top it up, understanding that topping it up dilutes the founders again. It is an unpleasant set of options and it is better identified in advance than discovered in a retention conversation.

When protection stacks up

Anti-dilution is usually discussed one round at a time, and it does not arrive one round at a time. By Series B a company can have three separate classes of preference shares, each with its own conversion price and its own protective clause.

A down round then triggers every one of them at once, each adjusting from a different starting price. The seed investor who paid ₹7 and the Series A investor who paid ₹26 receive very different adjustments off the same event, and the combined effect on the ordinary shares is larger than any single clause suggests.

Two practical consequences follow. The first is that the ordinary shareholders, meaning the founders and the pool, can be diluted considerably more than the headline down round implies once every adjustment has been made. The second is that the adjustments interact: shares issued to one protected class increase the total share count, which is an input to the weighted average formula for the others.

So the arithmetic has to be done on the whole cap table rather than clause by clause, and it needs doing in the order your documents specify. This is the point at which a spreadsheet stops being enough and the answer should come from whoever drafted the agreements.

The useful preparation is simply to know how many protective clauses you have and what each one says. Founders three rounds in are frequently surprised by the count, because each was agreed in a different negotiation and nobody has read them side by side since.

The wider point about down rounds

It is worth saying plainly that a down round is not a disaster and has become an ordinary event. Companies that raise at lower valuations and keep operating are in a considerably better position than companies that refuse to and run out of money.

What makes a down round damaging is rarely the valuation. It is the terms attached to it: ratchets, stacked preferences, pay-to-play provisions applied against founders rather than investors, and recapitalisations that reset the cap table entirely. Those are negotiated at the point of maximum pressure, which is why the protections you want are the ones agreed two rounds earlier.

So the useful framing for anti-dilution is not whether you will ever need to worry about it. It is that the clause is cheap to negotiate today and expensive to negotiate on the day it matters.

The cap table template on this site will hold the resulting share counts, and the liquidation waterfall calculator shows what the preference stack does at an exit once a down round has added another layer to it. Both are worth running before signing anything, and neither replaces having a lawyer read the document.

What to do this week

1. 01Find out what you have. Read the anti-dilution clause in your existing shareholders' agreement, and establish whether it is weighted average or a ratchet, and whether it is broad or narrow based.
2. 02Model it at a down round 40% below your last price, so you know the answer rather than the term.
3. 03Check whether pay-to-play applies, and to whom.
4. 04Check the carve-outs, particularly whether an ESOP top-up triggers an adjustment.
5. 05If you are holding a term sheet now, do all four before you sign it rather than after.

None of this requires a lawyer to start, and all of it should end with one. The value of doing the arithmetic first is that you arrive at that conversation with a specific question instead of a general worry.

About Simplify

Simplify is a finance clarity and investment readiness practice working with founders across India, built on six years inside startups. We write about the questions founders bring before a decision, not after it.