A divorce settlement may be ineffective because of a mistake about its common basis only in limited circumstances. Section 1385 of the Austrian Civil Code sets a clear boundary: the mistake must concern the essential nature of the person or the subject matter. A later unfavourable development does not automatically meet that test.
The review therefore starts with the specific fact on which both parties are said to have relied when settling the case. The wording of the court record, the negotiations before it and the question whether uncertainty was consciously dealt with are equally important. An original mistake must be separated from a later change in circumstances and from a dispute about the meaning of the clause.
This article explains which questions arise when a divorce settlement is said to rest on a wrong common basis, which evidence can help and why section 1385 does not provide an automatic solution for every disappointing result after a divorce agreement.
Which review fits your divorce settlement?
This short check separates a possible original mistake from later changes and a dispute about the wording.
Already know you want to get in touch? Go straight to the enquiry form.
What became unclear after the settlement?
Choose the description that best matches the timeline and the point in dispute. The check does not replace a review of the complete court file.
Overview of all answers.
Prove the common basis and the original mistake
Prepare a chronology of the fact on which both parties are said to have relied when the settlement was made. Record how that assumption affected the settlement and assess the documents against section 1385 of the Austrian Civil Code.
Separate a later change from the original mistake
Record when the later change occurred and compare that date with the date of the settlement. A new financial, family or economic development is a separate question at first and is not automatically a mistake under section 1385.
Assess uncertainty that was consciously accepted
Read the clause together with the negotiation documents. If an open question was expressly made part of the settlement or a risk was recognisably accepted, that may weigh against a relevant mistake. The precise wording remains decisive.
Review the settlement content and implementation separately
Compare the court record, annexes and later implementation. A dispute about the meaning of a clause is initially an interpretation or performance question. Only then should it be assessed whether a false common basis under section 1385 is also being claimed.
What a mistake in a divorce settlement concerns
Section 1385 of the Austrian Civil Code deals specifically with a mistake in a settlement. Its wording provides that a mistake can make the settlement invalid only insofar as it concerns the essential nature of the person or the subject matter. The rule therefore focuses on the content of the agreement and the quality of the mistake.
In a divorce settlement, the first step is to identify the provision affected. It may concern a payment, a transfer of an asset or another obligation recorded in the settlement. Calling a fact the basis of the settlement does not by itself establish that section 1385 applies.
Later dissatisfaction with the result is not enough. A mistake about one’s negotiating position, an optimistic valuation or a simple calculation error must be distinguished from a mistaken assumption about an essential quality of the person or the subject matter. The classification depends on the facts.
When the settlement has a common factual basis
A common basis describes a fact or expectation on which the parties say their agreement rested. It is not enough that one party privately held that view. The review must show which assumption actually mattered for the settlement and whether it was recognisable to the other party.
In a divorce settlement, the alleged basis may concern the value of an asset, an existing obligation or a legally relevant personal characteristic. These are examples, not conclusions. The clause, the negotiations and the evidence of the parties’ knowledge at the time remain decisive.
The parties may also settle precisely because the facts are uncertain. In that case, the uncertainty itself forms part of the agreement. A party who later regrets the result of that uncertainty must explain why there was nevertheless a material false assumption shared by both sides.
How an original mistake differs from a later change
For section 1385, the time of the settlement matters. A fact that arises only later was not already wrong when the agreement was concluded. Subsequent unemployment, a fall in value or a changed care arrangement cannot therefore be treated solely as a mistake in the original settlement basis.
The timing is different if the relevant fact already existed at conclusion but both parties assumed another state of affairs. The knowledge at that time then has to be reconstructed. The later discovery explains when the discrepancy became known, but it does not by itself prove its legal significance.
This distinction prevents every post-divorce burden from being reclassified retrospectively as a mistake in the settlement. Later developments may raise other family-law questions depending on the agreement. Those questions must be reviewed separately from a claim based on a mistake about the settlement subject matter.
Four questions separate mistake, risk and interpretation
The distinction shows which fact must be examined first in each situation.
| Review point | Specific question | Importance for the next review |
|---|---|---|
| Timing | Did the alleged fact already exist when the settlement was made? | A later change must be separated from an original mistake. |
| Common basis | Did both parties rely on the same basis? | A private assumption alone does not describe a common settlement basis. |
| Subject matter | Does the mistake concern the essential nature of the person or subject matter? | Section 1385 requires an essential connection to the settlement object. |
| Risk | Was the uncertainty consciously accepted in the settlement? | The wording and negotiations may weigh against a later mistake argument. |
This table provides initial orientation. The complete court record and negotiation documents remain decisive.
Why the wording of the court record matters
The recorded settlement is the starting point. It shows which payments, conditions and declarations were agreed. Annexes, attachments and calculations expressly incorporated into the settlement belong in the same review. A single note from a conversation cannot replace the complete text.
It is especially important to see whether the settlement expressly mentions an open uncertainty. Wording about a final settlement, a reservation or an identified unknown circumstance may determine the scope of the agreement. Its meaning can be assessed only in the complete context.
An unclear term is initially an interpretation problem. The parties must then establish what the declaration means according to its wording and circumstances. Such a dispute is not automatically a mistake about the settlement basis. Section 1385 becomes an additional question only if a false common assumption is also alleged.
How to prove the mistake and common settlement basis
A party relying on a relevant mistake should be able to state the alleged fact in one clear sentence. The next step is to show when it was known, what common assumption followed and where that assumption affected the settlement. General references to an unfair result are too vague for this purpose.
Useful evidence can include the court file, settlement drafts, annexes, calculations, emails and messages from the negotiations. Statements by the participants or reliable documents concerning the asset or person may also help. The evidence should show the common view at the time, not merely the later discovery.
Arrange every document by date and function. One document may concern the value of an asset, another the parties’ knowledge and a third the effect on the agreement. This separation makes the review clearer and prevents a later document from being mistaken for direct evidence of the earlier common intention.
The decisive chronology in five steps
A timeline connects the fact, the settlement and the later discovery.
Identify the fact
Describe the alleged quality of the person or subject matter concretely and without conclusions.
Record knowledge
Document what both parties knew or assumed before and at the settlement.
Explain the effect
Show which clause or obligation would allegedly have been different without that assumption.
Date the discovery
Record when and how the discrepancy from the assumed state became known.
Classify the consequence
Assess section 1385 against interpretation, later change and any other relevant issue.
Which part of the settlement may be affected
Section 1385 says that a mistake can make the settlement invalid only insofar as it concerns the essential nature of the person or subject matter. The claim therefore needs a precise allocation: which provision depends on the alleged false basis and which provisions stand independently?
A divorce settlement may combine several subjects in one court record. A payment, a transfer of an asset and an arrangement for the children each involve different facts. A dispute about one point therefore does not automatically determine the effect on every other agreement.
Partial effect should not be assumed too quickly. First review the connection between the clauses. Also check whether the parties treated the agreement as a comprehensive settlement. The scope and the appropriate procedural step require a separate review of the full settlement.
Important: A later deterioration, a lower value or a disappointing negotiation result does not itself prove a mistake under section 1385. The relevant points are the common basis at conclusion, its importance for the settlement subject matter and the contemporaneous evidence.
Which documents to prepare for the review
First secure the complete court record with all annexes and the latest settlement draft. Add payment records, handover documents, certificates and the messages in which the relevant fact or its uncertainty was discussed.
Then prepare a short table with the date, event, assumption at the time, participants and evidence. Mark whether each document arose before the settlement, on the day of conclusion or later. This makes it possible to see whether the alleged basis existed when the parties agreed.
Before making a declaration of invalidity or filing in court, review the structure of the complete settlement. Clarify which provision you seek to correct and what an argument would mean for payments or transfers already made. A reliable assessment requires the full file.
Mistake and common basis in a divorce settlement
When can a mistake make a divorce settlement invalid?
Section 1385 of the Austrian Civil Code sets a narrow condition: the mistake must concern the essential nature of the person or subject matter. The common basis at conclusion and the specific part of the settlement affected must also be established.
Is it enough that the settlement later turns out to be unfavourable?
A later unfavourable development or an incorrect economic estimate is not automatically enough. The review must first establish whether an existing, essential assumption shared by both parties was wrong when the settlement was made.
What if both parties knowingly accepted an uncertainty?
The wording and negotiation documents then become particularly important. An uncertainty consciously addressed in the agreement may weigh against a later mistake claim. The answer depends on the actual declaration and context.
Which evidence matters for a mistake in a settlement?
Keep the court record, drafts, annexes, calculations, messages, emails and contemporaneous documents. They should show what fact both parties assumed at conclusion and why it mattered to the agreement.
Can a mistake affect only part of a divorce settlement?
Section 1385 refers to invalidity only insofar as the mistake concerns the essential nature of the person or subject matter. Whether clauses can be assessed separately depends on their connection and on the complete settlement text.
Further information on divorce settlements
Reviewing a divorce settlement after the hearing
Check wording, correction and implementation after a court hearing.
Settlement with an equalisation payment and security
Review due dates, safeguards and the consequences of late payment.
Implementing a divorce settlement
Assess land register, bank and insurance steps after an agreement.
Amicable divorce
Prepare the central points before a joint divorce application.