Protecting Your Business Before Marriage: How Prenuptial Agreements Safeguard Company Shares

23/09/2026

For most owner-managers, the company is the largest asset they hold and the hardest one to divide. On divorce, the court treats a shareholding like any other resource. Unlike a house or a pension, though, it cannot be split down the middle or sold at short notice without damaging the very thing being valued.

Founders usually plan carefully for every other risk to their shares. Shareholder agreements, articles of association, investor protections and succession arrangements are all routine. The end of a marriage rarely makes that list, despite being one of the events most likely to force a sale.

The tool for dealing with it in advance is a prenuptial agreement. In England and Wales, pre-nuptial agreements are not automatically binding, but they carry considerably more weight than most business owners assume — and the law around them is, for the first time in over a decade, on the move.

What Actually Happens to Shares on Divorce

When a marriage ends, the court’s task under the Matrimonial Causes Act 1973 is to achieve a fair outcome given the resources available to both parties. Company shares are resources. They sit on the schedule of assets alongside the house, the pension and the savings.

That creates two problems peculiar to business owners. The first is valuation: a private company has no share price, so the court relies on expert accountancy evidence, and valuing a business whose worth largely walks out of the door with its founder is an inexact science conducted at considerable expense.

The second is liquidity. A settlement may award a spouse a sum reflecting shares that cannot be sold, or cannot be sold without destroying the business. Courts have tools here — offsetting the value against other assets, ordering a transfer of shares, structuring payments over time — but each has consequences. Offsetting may mean surrendering the family home. A transfer can leave an ex-spouse on the register of a company they have no involvement in, which rarely suits anyone, least of all co-shareholders. Deferred payments tie the business to an obligation for years.

Owning It First Is Not Automatic Protection

A common assumption is that a business built before the wedding is simply out of scope. The position is more nuanced, and was clarified by the Supreme Court in Standish v Standish [2025] UKSC 26, handed down in July 2025.

The court confirmed a meaningful distinction between matrimonial property — broadly, the fruits of the marriage, shared equally as a starting point — and non-matrimonial property, such as assets brought into the marriage, inheritances and gifts. The latter is not subject to the sharing principle in the same way.

The qualification is the concept of “matrimonialisation”. Pre-owned assets can shift into the matrimonial category where the parties have treated them as shared. For a business, the routes are not exotic: a spouse takes a role, however informal; shares are transferred for tax planning; profits are reinvested rather than drawn; the company funds family life so completely that it becomes indistinguishable from the joint finances.

A twenty-year marriage during which a business grew from a spare room to a substantial company poses a genuinely difficult question about how much of that growth is matrimonial. Commentary on Standish has emphasised that a nuptial agreement remains the clearest way to settle that question in advance.

What a Prenup Can — and Cannot — Do

Prenuptial agreements are not automatically binding in England and Wales. Since the Supreme Court’s decision in Radmacher v Granatino in 2010, the position has been that the court should give effect to an agreement freely entered into by both parties with a full appreciation of its implications, unless it would be unfair to hold them to it.

In practice, a well-made agreement is highly persuasive and frequently decisive. One limit, though, is absolute: it cannot leave a spouse or the children of the family without their needs met. If the company is the only substantial asset, ring-fencing it entirely may not survive contact with that principle. The realistic goal is not total exclusion but controlled exposure — protecting the shareholding and the founder’s control while making clear provision for the other spouse from elsewhere.

What Makes an Agreement Hold Up

The difference between an agreement that works and one that unravels usually lies in the drafting detail. The procedural safeguards are the foundation — free entry, full disclosure on both sides, separate independent advice, execution well ahead of the wedding. Signing a month before the ceremony is the minimum; three to six months removes any argument about pressure.

The business-specific provisions are where protection is won or lost:

Define what is protected. The shares, or the shares plus future growth? Dividends, or only capital value? Retained profits never drawn?
Deal with change. Founders rarely hold the same shareholding for twenty years. Anticipate new share classes, dilution, restructuring and a sale.
Agree the valuation approach now, rather than fighting about methodology later.
Address the spouse’s contribution. If they may work in the business, or give up a career for the family, say what happens — silence invites argument.
Read it against the company’s articles and shareholder agreement. Pre-emption rights and compulsory transfer provisions triggered by divorce interact with what a family court might order; where they conflict, nobody wins.

Raising It Without Wrecking the Mood

The awkwardness is real, and worth naming. The framing that works is the one that is true: this is not about anticipating failure, it is about protecting the people who depend on the business — employees, co-owners, and the couple themselves — from a decision made by a court under pressure, years from now, on a valuation neither of them agrees with.

Handled early, with both parties properly advised, it is a planning exercise much like a will or a shareholder agreement.