When is a marital agreement invalid?

When does a marital agreement fail in court?

A marital agreement becomes invalid when two things come together. Objectively, it has to burden one side unfairly, and subjectively, that side has to have been in a weaker bargaining position when the agreement was signed. If either one is missing, the agreement stands, even if it divides things unevenly.

The review has two stages. Validity review looks at the day of notarization § 138 (1) BGB, exercise review at the day one side relies on the agreement § 242 BGB. The two stages lead to different legal consequences, and that difference decides what is left of an agreement under challenge.

How strongly each consequence of divorce is protected

Germany’s Federal Court of Justice ranks the consequences of divorce by how close they sit to the core area of divorce law BGH, judgment of February 11, 2004, XII ZR 265/02. The closer a consequence sits to that core, the tighter the limits on freedom of contract. From the inside out:

• Maintenance for the care of shared children sits closest to the core. It serves the child first and foremost and is largely beyond the reach of an agreement.
• Maintenance for old age and illness comes next. Both protect against risks nobody can control.
• The Versorgungsausgleich (pension rights adjustment) ranks alongside those two, because in substance it is old-age maintenance paid in advance.
• Maintenance for unemployment, top-up maintenance and maintenance for education sit further out and can be arranged much more freely.
• The Zugewinnausgleich (equalization of accrued gains) sits furthest out. It is the most open to free agreement, which makes it the most rewarding area for planning ahead.

This ranking explains a finding that regularly surprises clients. An agreement that excludes the Zugewinnausgleich (equalization of accrued gains) entirely holds up more often than one that makes a small cut to maintenance for the care of children.

Validity review under § 138 (1) BGB

The first stage asks whether, on the day of notarization, the agreement already divided the burdens so unfairly that the law has to refuse to recognize it. The yardstick is an overall assessment of income, assets, the planned shape of the marriage and the effects on shared children.

In 2025, the Federal Court of Justice sharpened where that line runs BGH, decision of May 28, 2025, XII ZB 395/24. In 2010, a business economist who was running her own limited company at the time signed an agreement with a shareholder in several family businesses. It provided for Gütertrennung (separation of property), the exclusion of the equalization and a mutual waiver of inheritance and compulsory share rights. After the birth of their third child, she gave up her career. When they separated, she argued that the agreement was contrary to public policy.

The court did not agree with her. An unequal distribution of assets and a traditional division of roles do not by themselves make a marital agreement contrary to public policy. It takes aggravating circumstances outside the deed: exploiting a predicament, social or economic dependence, or intellectual inferiority. Where these are absent, the agreement stands.

Two details of this case tend to get lost in short summaries, and for drafting they matter more than the headnote. The wife had her own lawyer when the agreement was notarized and was financially independent. And the agreement by no means left her empty-handed on maintenance. Once the marriage had lasted four years, it promised her €5,000 a month, adjusted for inflation. On top of that came maintenance for the care of the children, with no obligation to work until the youngest turned seven. When an exclusion of the equalization holds, it rarely stands alone.

If validity review does apply, the clause concerned is void from the start. The statute takes its place, meaning the full statutory standard the agreement was meant to avoid.

Exercise review under § 242 BGB

The second stage comes into play later and asks whether circumstances have shifted so much since notarization that relying on the agreement today would be an act of bad faith. The measure is what the spouses planned together at the time.

The classic case is the marriage that turned out differently than planned. Two working spouses agree to waive maintenance from each other because both earn well and neither depends on the other. Then a child arrives, one of them gives up work, and the planned two-income marriage becomes a one-income marriage. The waiver now hits someone it was never meant to hit under the shared plan.

The consequence here is milder. Instead of throwing out the agreement as a whole, the court adjusts the legal consequence to what would be fair without the shift.

Which circumstances count as inferiority

Inferiority means a situation that can be named, not dissatisfaction with the result after the fact. Germany’s Federal Constitutional Court set the starting point BVerfG, judgment of February 6, 2001, 1 BvR 12/92. Where a marital agreement reflects not a negotiation between equals but the one-sided dominance of one side, the courts have to correct it through the general clauses of civil law.

As the typical example of such a situation, the court names the unmarried pregnant woman who has to choose between raising the expected child alone and marrying the father. The man’s willingness to marry is not, on its own, enough in return for giving up everything she would be entitled to on divorce.

In our practice, four situations come up again and again:

• The draft arrives a few days before the wedding, long after the invitations went out.
• One side barely speaks the language of the agreement and has not received a written translation.
• One side’s residence permit depends on the marriage continuing.
• Only one side had a lawyer, and the draft came from that very lawyer.

We often hear that the notary explained everything to both of you, so all must be in order. A notary explains the content of the deed and its legal scope. Whether that content is good for you is not something the notary may judge for one side, because the notary owes the same duty to both. That is exactly the one-sided advice that is missing.

What happens when a single clause fails

Once one clause fails, the rest of the agreement is open to question. Where a clause is contrary to public policy, the entire agreement is void in case of doubt § 139 BGB. The rule is different if it can be shown that the spouses would have wanted the remaining part even without the void one.

That is why almost every notarized marital agreement contains a severability clause that says exactly that. It helps, but it does not decide the matter on its own. Where the one-sidedness comes precisely from several waivers working together, what remains rarely survives the overall assessment.

Under exercise review, by contrast, the agreement stays in place. The court replaces only the one legal consequence a side invokes in bad faith and leaves everything else untouched.

What makes a marital agreement hold up

A marital agreement holds up above all because of the way it came about, and less because of its wording. Four points carry the most weight:

• Several weeks between the first draft and the notary appointment. Before a wedding, the whole process belongs several months ahead of the date.
• Separate legal advice for both sides, and documented.
• A visible counter-benefit for the side that gives something up, such as a lump sum, a property or a staggered maintenance arrangement.
• A preamble recording the purpose of the agreement and the financial situation of both sides at signing. Years later, it is the best evidence of what was actually discussed.

Because exercise review responds to later shifts, a second look pays off after every major change, such as the birth of a child, taking over a business or a move abroad. How an existing agreement can be adjusted is covered in Changing or canceling a marital agreement.

How much room the individual levers leave is set out in detail in Excluding the equalization of accrued gains by marital agreement and in Settling post-marital maintenance in a marital agreement. Our page on the marital agreement describes the overall framework.