On 12 December 2025, the Court of Cassation issued a ruling (the "Tiger Group" case) that clarifies a recurring practical question in co-ownership management: can the owners' association take legal action for hidden defects on behalf of individual co-owners? The answer is no — and the implications for syndics and property managers are immediate.
What did the Court of Cassation decide on hidden defects in co-ownership?
The owners' association (ACP) does not have standing to bring the hidden defects warranty claim on behalf of individual co-owners, even when the defect affects common areas. Each co-owner must act individually — or as part of a coordinated class action outside the ACP — to assert their rights against the seller or developer.
This ruling of 12 December 2025 (probable ref. C.24.0179.F) clarifies a legal grey area that syndics and property managers had often relied upon, whether out of convenience or by mistake.
Reminder: what is a hidden defect under Belgian law?
A hidden defect is a defect in an immovable property that:
- Existed at the time of sale (or delivery in the case of new construction)
- Was not apparent at the time of sale — a normally prudent buyer could not have detected it
- Makes the property unfit for its intended use, or significantly diminishes that use
- Would not have been accepted by the buyer, or would have led to a lower price, had it been known
The hidden defects warranty is a contractual action: it is based on the sale contract (or construction contract) and engages the liability of the seller (or developer).
The "short period": an absolute urgency
The element that makes this ruling particularly important is the time limit. The hidden defects warranty must be exercised within a "short period" from the discovery of the defect. This period is not fixed by law in days or months: it is assessed on a case-by-case basis by the court in light of the circumstances. In practice, courts often consider a period of more than a few months after discovery to be excessive.
If co-owners believed, incorrectly, that the ACP was acting on their behalf, and then discovered on reading the ruling that this was not the case, they could find themselves out of time. This is the concrete risk that this ruling creates for ongoing cases.
What the ACP can and cannot do
What the ACP can do
The owners' association has legal personality and can take court action within the scope of its legal missions. It can in particular:
- Act for the conservation, maintenance, and administration of common areas
- Bring actions concerning common charges (recovery of arrears)
- Bring actions for nuisance affecting common areas
- Take urgent protective measures (judicial expert assessment, interlocutory proceedings)
- Act in the event of construction defects affecting common areas (under the decennial warranty — distinct from the hidden defects warranty)
What the ACP cannot do (after the ruling of 12 December 2025)
The ACP cannot substitute itself for individual co-owners in bringing the hidden defects warranty claim. Even if the defect affects a common area (the roof, the main pipes, the façade), it is for the co-owners as individuals to act — not for the ACP as a distinct legal entity.
The fundamental distinction between the decennial warranty and the hidden defects warranty:
| Criterion | Decennial warranty | Hidden defects warranty |
|---|---|---|
| Legal basis | Art. 1792 Civil Code | Art. 1641–1649 Civil Code |
| Who can act | ACP for common areas | Individual co-owners |
| Time limit | 10 years from completion | Short period from discovery |
| Liable party | Architect + contractor | Seller or developer |
| Type of defect | Structural soundness | Hidden defect making the property unfit |
Why this ruling changes practice for syndics
The risk of confusion
Before this ruling, some syndics brought court actions in the name of the ACP for hidden defects, believing — or hoping — that this route was available. The ruling of 12 December 2025 definitively closes that door.
Consequences for ongoing cases:
- An action brought by the ACP for hidden defects risks being declared inadmissible
- Co-owners who relied on the ACP may have lost their right to act individually (short period exceeded)
- A syndic who did not inform co-owners of this limitation could see their professional liability engaged
The syndic's duty to inform
After this ruling, the syndic has a clear obligation: inform co-owners of the existence of a potential hidden defect and the need to act individually (or collectively, but outside the ACP structure).
This information must be prompt, documented, and precise. It must include:
- A description of the defect identified
- The co-owners potentially affected
- A reminder of the need to act within a short period
- A statement that the ACP cannot act on their behalf
Procedure in case of a hidden defect affecting several units: practical guide
Step 1: Identify and document immediately
On discovery of a potential defect (by a tenant, a co-owner, during a routine inspection):
- Timestamped photos of the defect (before any intervention)
- Written report by the person who discovered it (name, date, description)
- Preliminary assessment of the impact (which units are affected, which common area)
- Keep all documents relating to the purchase or construction (sale deed, permits, completion reports)
Step 2: Inform co-owners without delay
The syndic sends written communication to all affected co-owners as soon as possible after discovery. This communication:
- Describes the defect identified and the units affected
- Sets out the legal framework (hidden defect, short period)
- Explicitly confirms that the ACP cannot act on their behalf (reference to the ruling of 12 December 2025)
- Recommends consulting a lawyer specialising in property law
Step 3: Facilitate collective action outside the ACP
If several units are affected, a collective action by individual co-owners is legally possible. It allows the procedural costs to be shared and a joint file to be built. The syndic can facilitate this coordination (list of affected co-owners, available archived documents) without assuming legal responsibility for it.
Step 4: Take protective measures if necessary
Alongside the co-owners' warranty claim, the ACP can still take urgent protective measures to prevent the defect from worsening: judicial expert assessment, emergency measures to stop infiltration, security measures.
These protective measures do not interfere with the hidden defects warranty claim — they complement it.
With Seido, every maintenance report is tracked with photos, date, and communication history. In case of a hidden defect affecting several units, the manager can quickly identify all co-owners concerned, centralise documentation, and prove the date of discovery — a decisive factor in meeting the "short period" requirement. Discover Seido →
This article is part of Property Essentials #2 — February 2026. Also read: Building manager and court proceedings: when does the AGM need to agree? — Energy renovation in co-ownership buildings: the real figures.
Sources and references
- Court of Cassation, 12 December 2025 (probable ref. C.24.0179.F) — the ACP does not have standing to bring the hidden defects warranty claim
- Co-ownership and hidden defects, DroitBelge.be
- Full text of the ruling: juportal.be
- Articles 1641 to 1649 of the Belgian Civil Code — hidden defects warranty