How to Split Equity Between Co-Founders (When You're Not Defaulting to Delaware)

Split equity by contribution, not by headcount — equal shares if founders join full-time at the same moment with comparable stakes, weighted shares if one founder carries more risk, capital, or prior work into day one. The split matters less than the vesting schedule that protects it: four-year vesting with a one-year cliff makes almost any honest split survivable, while an unvested split turns a single early departure into a cap table problem you can't undo. Everything else — option pool size, jurisdiction-specific paperwork, what to do when someone leaves — follows from those two decisions.

Most of what's written about this online assumes a Delaware C-corp, a US 83(b) election, and an option pool sized around IRS rules that don't apply everywhere. If you're incorporating in Riyadh, Lagos, Nairobi, or Jakarta, the framework holds — the mechanics underneath it don't. Here's both.

Equal split, weighted split, or negotiated split

There are really only three ways founders divide equity, and each one fits a different situation.

Equal split. Two or three founders, joining full-time on the same day, contributing comparable time, skills, and capital. An equal split avoids the harder conversation about relative value, and for founders at genuinely the same starting point, that's not avoidance — it's accuracy. The argument for equal splits over a company's first decade is forward-looking: the work ahead is larger than any early difference in contribution, so optimizing the split for month one wastes negotiating capital you'll need later.

Weighted split. One founder quit a job six months earlier to build the first version. One is putting in savings the others aren't. One has domain expertise or an existing customer relationship the company is built around. A weighted split tries to price those differences into the cap table on day one. It's the right call when the differences are real and large — but it's also where founders lose the most time, because there's no formula that converts "I started three months earlier" into a defensible percentage. Pick a rough number, document the reasoning, and move on. Precision here is a trap.

Negotiated split with vesting as the safety valve. This is what weighted splits become in practice once you accept that the exact number matters less than the protection around it. Instead of debating 62/38 versus 58/42 for another week, founders agree on something close, put every share on the same four-year vesting schedule, and let time — not a spreadsheet formula — validate the split. If someone's contribution turns out to be worth less than expected, they leave with an unvested balance still in the pool. If it turns out to be worth more, that's usually addressed later through a new grant, not by relitigating the founding split.

Why vesting matters more than the ratio

A cap table with an unvested co-founder is one of the most common reasons early-stage startups become hard to fund. Not because investors moralize about fairness — because a departed co-founder holding a large, fully-vested stake is a governance risk investors have seen before: someone with real ownership and zero ongoing obligation to the company, sitting on your shareholder registry indefinitely.

The standard structure is four-year vesting with a one-year cliff: nothing vests for the first twelve months, then 25% vests at once, then the remainder vests monthly or quarterly over the following three years. The cliff exists specifically to handle the founder who leaves in month three — without it, a few weeks of work could otherwise lock in years of equity.

Vesting doesn't need to be identical across founders to be fair. A founder joining eighteen months after incorporation can vest on their own four-year clock starting from their join date, layered on top of the original cap table, without disturbing what the first founders already earned. What breaks is skipping vesting entirely because "we trust each other" — trust isn't the failure mode vesting protects against. Divergent priorities, health, family circumstances, and slow-motion disagreements about the company's direction are.

Sizing the option pool

The founders' split isn't the only allocation on day one — there's also the option pool for future hires, and it dilutes everyone in the founding split proportionally, not just the company. A pool that's too small gets renegotiated during your first priced round, and investors typically ask for the top-up to come from the pre-money valuation — meaning the dilution lands entirely on founders, not on the new investor.

A pool of 10-15% of fully diluted shares is a reasonable starting range for a seed-stage company, sized against an actual 12-to-18-month hiring plan rather than a round number pulled from a template. Before you fundraise, model how many people you'll grant options to and roughly how much equity each role needs — an early engineering hire and a part-time advisor shouldn't be drawing from the same assumption.

What actually changes outside the US

The equity-split framework above is geography-independent. The paperwork underneath it isn't, and this is where most generic guides — written for a Delaware C-corp with a US-standard cap table — stop being useful.

Share issuance may require more than a board signature. In Saudi Arabia, issuing new shares or amending the capital structure can require a general assembly resolution under the 2022 Companies Law, not just board approval — a step a US-focused founders agreement template has no line for. Skipping it doesn't just create a compliance gap; it means the share issuance may not be validly recorded at all.

There's often no 83(b) equivalent. The 83(b) election is a US IRS filing that lets founders elect to pay tax on the value of restricted stock at grant instead of at vesting. It only exists because the US taxes unvested equity as ordinary income as it vests. Saudi Arabia and the UAE have no personal income tax, so there's no election to make and no 30-day deadline to track — a founders agreement built around 83(b) language is solving a problem that doesn't exist in those jurisdictions. Other markets have their own version: the UK's EMI scheme has different tax treatment entirely, and it's worth checking what — if anything — applies before assuming a US template covers it.

A Delaware flip means splitting equity twice. Founders raising from Western VCs often incorporate locally first, then flip into a Delaware or UK holding company once the first priced round is imminent. If that's your plan, the founding split needs to be mirrored precisely between the operating entity's cap table and the new holding company's cap table — a mismatch between the two, even a rounding difference, becomes a diligence flag for the round you're trying to close with the flip.

None of this changes who should own what. It changes what has to be true for the split to actually hold up once you formalize it — in a document, on a cap table, and eventually in front of an investor's lawyer.

Formalize it before you need to

An equity split that exists only as a conversation is not a split — it's a disagreement waiting for a trigger. Put it in a signed founders agreement covering the split, the vesting schedule, and what happens on departure, before there's a cap table to fight over. We've written a jurisdiction-specific breakdown of what that document needs to include for founders incorporating in Saudi Arabia, including why US-style 83(b) language doesn't apply.

Once the split and vesting schedule are agreed, the same discipline applies to every option grant that follows — for the pool, not just the founders. If you're weighing whether that needs a lawyer for every hire or just once at the start, here's the actual breakdown.

Govy tracks vesting schedules, cliffs, and option pool dilution on one append-only ledger, so the founding split and every grant that follows stay reconciled automatically instead of drifting apart in separate documents. See how it works at govy.tech.

FAQ

What is a fair equity split between co-founders?

There's no universal fair split — only a defensible one. Equal splits work when founders join full-time at the same moment from the same financial position; weighted splits work when one founder is carrying more risk, more prior IP, or more capital into day one. What makes either fair isn't the ratio, it's that every founder can explain the number without resentment a year later, and that it's protected by vesting so the split can survive someone leaving early.

Should co-founders always split equity equally?

No, but equal splits aren't automatically wrong either. They work well for two or three founders starting at the same time with comparable skin in the game, because the alternative — negotiating a precise weighting for pre-company contributions — often costs more in trust than the percentage points are worth. Where equal splits fail is when one founder joins months later, part-time, or with materially less at stake; forcing equality there just moves the resentment instead of avoiding it.

What happens to a co-founder's equity if they leave early?

It depends entirely on whether their shares were vesting. With a standard four-year vesting schedule and a one-year cliff, a co-founder who leaves after eight months walks away with nothing; one who leaves after eighteen months keeps roughly 37.5% of their allocation, and the rest returns to the pool for you to reissue. Without vesting, a departed co-founder keeps their full stake regardless of how long they stayed — a dead equity position that makes the next fundraise harder to close.

How big should the option pool be before fundraising?

Most seed-stage companies reserve 10-15% for a first pool, sized against a hiring plan for the 12-18 months after the round, not against how the founders feel about dilution today. Investors will ask for the pool to come out of the pre-money valuation, so an undersized pool gets topped up at the worst possible time — during term sheet negotiation, when the dilution lands entirely on the founders instead of being shared across the cap table.

Do equity split rules change outside the US?

The framework — equal or weighted split, four-year vesting, a sized option pool — doesn't change by geography. What changes is the paperwork underneath it. Issuing shares in Saudi Arabia can require a general assembly resolution a Delaware template has no line for; a UAE or KSA ESOP grant has no 83(b) election because there's no personal income tax to elect out of; and if you're flipping to a Delaware or UK holding structure, the split has to be mirrored correctly across two cap tables, not just one.