What Happens to a Business in a Prenuptial Agreement?
/If You Own a Business Before You Get Married
California law does not have a clear, automatic answer for what happens when one spouse runs a premarital business during the marriage and it grows. Courts can award the other spouse a share of that growth, and the outcome depends on expert witnesses, valuations, and a judge's discretion. That process is expensive, unpredictable, and often leaves both spouses feeling the result was unfair.
What a prenuptial agreement can do:
Keep it yours, fully. You and your spouse agree that the business, and everything it earns and grows into, stays your separate property. Your spouse gives up any claim to the business or its appreciation. This is the simplest option and the one with the least potential for future dispute.
Keep the business yours, but share the income. The business stays yours, but a portion of what it earns each year is treated as money belonging to both of you. You keep the equity and the long-term value; your spouse participates in the cash flow. This is a middle-ground option that works well when both of you want to feel the marriage is economically fair without putting the business itself at risk. One thing to know: defining "income" is harder than it sounds: a business owner controls how much money the business pays out versus keeps inside the company, so the agreement needs to be specific about how income is calculated to make sure this option works as intended.
Pre-agree on what counts as a fair return. Instead of letting a court decide later what portion of the business growth your spouse is entitled to, you agree on that formula now, while you're on good terms and both understand the business. This replaces an expensive courtroom battle with a calculation you both already approved.
If You Start or Buy a Business During the Marriage
In California, income earned during marriage generally belongs to both spouses. That means a business you build from scratch during the marriage could be considered jointly owned, even if your spouse had nothing to do with it. On the other hand, if both of you work to build it, the law may not fully account for that either. Couples are often surprised by this.
What a prenuptial agreement can do:
Treat it as belonging to both of you from day one. If you're building something together,or if the spirit of your marriage is that everything you create during it is shared,you can simply agree that any business started during the marriage is community property. Clean, simple, and consistent with how many couples actually think about their finances. If one of you puts in separate money to fund it, that person gets reimbursed first before the split.
Keep it separate, but share what it pays you. The business is yours, the equity, the long-term value, the upside. But your salary and bonuses from it belong to both of you. This option protects the business as an asset while ensuring your spouse benefits from your work during the marriage. One thing to know: defining "income" is harder than it sounds, a business owner controls how much money the business pays out versus keeps inside the company, so the agreement needs to be specific about how income is calculated to make sure this option works as intended.
Start it as yours, but let it gradually become shared. Think of this like an employment vesting schedule. The business starts as your separate property, but over time, typically up to ten years, a growing percentage becomes community property. If the business is sold, there's an acceleration that gives your spouse a fair share of what had been building up. This option works well when one spouse is the founder and builder, but both want to feel that a long marriage is reflected in how the business is treated.
If You're Making Investments in Someone Else's Business
If you invest your own money in a startup or small business during the marriage, questions can arise about whether that investment and its returns belong to you, to both of you, or somewhere in between, especially if you later get more involved in running it.
What a prenuptial agreement can do:
Passive investment stays yours. If you put in your own money and stay hands-off, the investment and whatever it earns stays your separate property.
Active involvement changes the picture. If you later roll up your sleeves and start working in that business, the agreement can provide that at that point it becomes a shared asset,with you getting reimbursed for what you originally put in.
The right choice depends on a few practical questions:
How involved will both of you be in the business?
How important is simplicity?
What feels fair to both of you right now?