Adverse possession: 30 centimetres behind a garage

Boundary disputes rarely arise from ill will. Usually someone put up a wall decades ago, everyone involved took it to be the boundary, and nobody measured. The difference only becomes apparent when someone wants to build.

The facts

A garage was built on a plot of land in the early 1970s. Its rear wall stands roughly 30 centimetres away from the actual boundary – so the narrow strip behind it formally belongs to the neighbouring plot. It cannot, however, be reached from there: there is no way around the garage. For decades the strip was entered and used exclusively from the other side. The owner and her predecessors in title assumed that the wall stood directly on the boundary.

In 2022 a property developer acquired the neighbouring plot and initiated proceedings to alter the building plot and to obtain a building permit. What had been taken for granted for decades thus turned into litigation. Neither plot is entered in the Grenzkataster (the binding Austrian boundary cadastre).

The legal question

The claimant sought a declaration that she owned the strip, together with the defendant's consent to the corresponding entries in the land register, relying on Ersitzung (acquisitive prescription). She also sought an injunction restraining certain assertions in the building permit proceedings.

Acquisitive prescription is the acquisition of a right through qualified possession over the period laid down by statute. For ownership it requires sole possession of the thing – that is, actual control and the intention to possess. Control is not understood in merely physical terms; what matters is the outward appearance of dominion over the thing according to general understanding. The intention to possess shows itself in conduct of the kind an owner typically displays.

Important in practice: non-independent parts of a plot can also be acquired by prescription – provided the plot is not entered in the Grenzkataster (RS0011696). Where the boundary cadastre applies, that route is closed.

The decision

The Supreme Court admitted the extraordinary appeal on a point of law because the appellate court had, among other things, wrongly assessed the good faith of the claimant and her predecessor in title. A person acts in good faith who has respectable grounds for assuming that the thing belongs to them – and someone who shares the assumption that the garage wall stands on the boundary for decades is not automatically in bad faith.

The judgments of the lower courts were set aside in so far as they concerned the declaration of ownership and the consent to registration, and the case was remitted to the court of first instance for further proceedings. The dismissal of the injunction claim, by contrast, was upheld and became a partial judgment.

What follows from this

Anyone buying land on which they intend to build should have the actual course of the boundary checked rather than relying on walls and fences. Conversely, it is worth clarifying early on what a decades-long exclusive use of an area is based on. An entry in the Grenzkataster creates certainty – but it also rules out acquisitive prescription for the future.