Boundary Survey between Co-owners: Claim Inadmissible According to the Court of Cassation

Imagine the scene: you own a flat in Annecy, with a small adjoining garden. Your neighbour, also a co-owner, decides to erect a fence that encroaches on what you believe to be your land. You want an amicable boundary survey, but he refuses. So you take the matter to court. Problem: the court tells you that your claim for a boundary survey is inadmissible. Why? Because you are co-owners of the same plot, and a boundary survey is reserved for owners of distinct plots. This is exactly what the Court of Cassation recalled in a judgment of 19 November 2015 (No. 14-25.403).

This decision, handed down by the Third Civil Chamber, may seem technical, but it has very concrete consequences for thousands of co-ownership property owners. Indeed, a boundary survey is an action aimed at fixing the boundaries between two neighbouring parcels (land) belonging to different owners. But what happens when both parcels derive from the division of the same plot and are still held in undivided ownership (i.e., collectively owned by several persons)? The Court answers: the boundary survey action is inadmissible because one cannot survey co-ownership lots against each other.

So, how can you enforce your rights if a co-owner encroaches on your lot? This article explains everything step by step, with concrete examples in Lyon and Annecy. We will look at the facts of the case, the judges' reasoning, what changes for you, and above all how to avoid this type of dispute.

The Facts: A Story That Happens Every Day

The case began in a co-ownership property located within the jurisdiction of the Lyon Court of Appeal. Mr. X, owner in Annecy of a co-ownership lot including a part of the land, summons another co-owner, Mr. Y, for a boundary survey. Both lots derive from the division of a plot registered as AE. But between their two lots lies a plot consisting of a path, which remained in undivided ownership (i.e., belonging to all co-owners, not allocated to any specific lot).

Mr. X believes that Mr. Y encroached on his part of the land by building a fence. He therefore asks the Tribunal de Grande Instance to fix the boundaries between their respective lots by means of a judicial boundary survey. Mr. Y, for his part, challenges the admissibility of this action. According to him, a boundary survey is only possible between distinct parcels belonging to different owners. Here, the lots derive from the same plot and the disputed plot (the path) is undivided: there are therefore no boundaries to fix between co-ownership lots.

The court rules in favour of Mr. Y and declares the action inadmissible. Mr. X appeals, but the Lyon Court of Appeal upholds the judgment. Mr. X then appeals to the Court of Cassation. The Court of Cassation, in its judgment of 19 November 2015, dismisses the appeal and validates the lower judges' reasoning. It recalls that a boundary survey action is a real immovable action (relating to a right of ownership) and requires that the two parcels be distinct and belong to different owners. In this case, the co-ownership lots are not distinct parcels within the meaning of a boundary survey, because they result from the division of the same plot and are subject to the co-ownership regime.

What few people know is that this decision is part of consistent case law. Already in 2012, the Court of Cassation had ruled that "the boundary survey action is not available between co-owners of lots derived from the division of the same plot" (Civ. 3e, 13 June 2012, No. 11-16.939). The 2015 judgment merely confirms this rule.

The Reasoning of the Court — Deconstructed

To understand the decision, you must first know what a boundary survey is. A boundary survey is an operation that consists of officially fixing the boundaries between two neighbouring properties. It is regulated by Articles 646 and 647 of the Civil Code, which provide that any owner may compel his neighbour to carry out a boundary survey of their adjoining properties. The boundary survey action is therefore a personal action (arising from neighbourhood) but also a real action (relating to the land).

But beware: a boundary survey requires that the two parcels be "divided" (separate) and belong to different owners. In co-ownership, lots are not independent parcels: they are private parts of the same plot, subject to a co-ownership by-laws. The boundaries between lots are defined by the by-laws and the division description. If one co-owner encroaches on another, it is not a boundary survey problem, but a disturbance of enjoyment or a breach of the co-ownership rules.

In the case decided, the Court of Cassation noted that the disputed plot (the path) was held in undivided ownership among all co-owners. In other words, no one was its exclusive owner. Consequently, there were no two distinct parcels to survey: the lots of Mr. X and Mr. Y were part of an undivided whole, and the boundary between them was not a property boundary in the legal sense, but a mere delimitation of lots.

The judges therefore applied the following rule: a boundary survey action is inadmissible between co-owners of lots derived from the same plot, especially when common parts (such as the path) are held in undivided ownership. The only remedy available to Mr. X was to act on the basis of neighbourhood disturbance or breach of the co-ownership rules, but not a boundary survey.

In short, the Court made a fundamental distinction between individual ownership (a land of one's own) and co-ownership (a lot within a building). Boundary surveys are for individual land; for co-ownerships, other legal tools must be used.

What This Changes for You — Concretely

This decision has very important practical implications for owners, buyers, landlords and tenants in co-ownership.

For co-owners: If you believe another co-owner is encroaching on your lot (e.g., a fence or construction that extends beyond), you cannot bring a boundary survey action. Your remedy is to sue for breach of the co-ownership rules or for abnormal neighbourhood disturbance. For example, in Lyon, a co-owner whose neighbour built a terrace encroaching on his private garden succeeded by showing that the by-laws prohibited constructions without authorisation from the general meeting.

For buyers: Before buying a co-ownership lot, carefully check the division description and the co-ownership by-laws. The boundaries of your lot are described there. If you are unsure of the exact location, hire a surveyor for a survey, but know that this will not be an official boundary survey (since that is not possible between lots). If the seller has encroached on common parts or another lot, this may be a hidden defect (a non-apparent defect that makes the property unfit for use) and you can claim a price reduction or annulment of the sale.

For landlords: If you rent out a co-ownership lot, it is the tenant who suffers the disturbance. But it is up to you, as owner, to take action against the encroaching co-owner. You cannot demand a boundary survey, but you can sue the co-owner for non-compliance with the co-ownership rules. For example, in Annecy, a landlord obtained €5,000 in damages because the neighbouring co-owner had installed a garden shed on the common part adjoining the rented lot.

For tenants: You do not have standing to bring a boundary survey action because you are not the owner. But you can report the encroachment to your landlord, who must take the necessary steps. If the disturbance is serious (e.g., your access is blocked), you can request a rent reduction or termination of the lease.

In summary, this decision prevents you from using a boundary survey between co-owners, but it does not deprive you of all remedies. Act quickly: legal actions have time limits (5 years from the date you became aware of the disturbance for personal actions, 30 years for real actions).

Four Tips to Avoid This Type of Dispute

• Consult the co-ownership by-laws and the division description. Before any purchase or before modifying your lot, check the exact boundaries of your lot and the common parts. These documents are available from the managing agent. If they are imprecise, request a modification at a general meeting.
• Hire a surveyor for a topographical survey. Even if an official boundary survey is not possible, a surveyor can establish a precise plan of your lot and the common parts. This document can serve as evidence in case of dispute. Cost: between €1,000 and €3,000, depending on complexity.
• Prefer conciliation before litigation. If you notice an encroachment, first try to discuss with the co-owner. Propose mediation or judicial conciliation (free). In Lyon, the Chamber of Notaries also offers amicable mediations.
• Keep all evidence. Photos, letters, bailiff's reports, plans, minutes of general meetings: all can be useful. If the disturbance persists, you can take the matter to the Tribunal Judiciaire, but on a ground other than boundary survey.

Further Reading: Related Case Law and Developments

The Court of Cassation has rendered several judgments in the same vein. Besides the 2012 judgment already cited, mention may be made of a judgment of 27 March 2013 (No. 12-15.122) which ruled that "the boundary survey action is not available between owners of co-ownership lots, even if those lots are located on distinct plots, as long as they belong to the same co-ownership". The trend is therefore very clear: boundary surveys are reserved for individual properties.

However, if the lots are located on different cadastral plots and there is no undivided ownership, a boundary survey might be possible. For example, if two neighbouring co-ownership buildings have unclear boundaries, a boundary survey between the two co-ownership syndicates is admissible. This was recalled by the Court of Cassation in a judgment of 4 July 2019 (No. 18-18.942).

This case law could evolve if the legislature intervened, but for now, it is well established. The courts are very strict on the admissibility of boundary surveys. So, if you are a co-owner, forget about boundary surveys and focus on the co-ownership rules.

Checklist Before Taking Action

FAQ: The Questions You Are Asking

• Can I carry out an amicable boundary survey with my co-owner neighbour? No, because an amicable boundary survey also requires two distinct parcels. However, you can sign an amicable agreement on the boundaries, but it will not have the force of an official boundary survey. Have it homologated by the court if necessary.
• What should I do if a co-owner encroaches on my lot? You must act on the basis of neighbourhood disturbance (Article 1240 of the Civil Code) or breach of the co-ownership rules. Seise the Tribunal Judiciaire of the location of the building. Beware of the time limit: 5 years from the date you became aware of the disturbance.
• What are the costs of a legal action for encroachment? Lawyers' fees vary from €1,500 to €5,000 depending on complexity, plus expert fees (surveyor, bailiff) and court costs. If you win, the co-owner may be ordered to reimburse part of them.
• Can I demand the demolition of an encroaching structure? Yes, if it is irregular. But the judge may prefer damages if demolition is disproportionate. For example, if the structure is recent and the encroachment is minimal.
• What if the managing agent does nothing? You can sue the managing agent for failure to act. But it is better to first put the matter on the agenda of the general meeting.

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