Swiss pre-emption right, two Vaud towns lose in court

Two Vaud municipalities tried to step into a signed sale in the buyer’s place. The Federal Supreme Court turned them down twice in 2025, once over a date, once over a price.

Two municipalities lost on procedure, not on purpose

Le Mont-sur-Lausanne and Avenches each exercised a pre-emption right over a plot of land, and each lost before the Federal Supreme Court in 2025. Neither ruling questions what the two municipalities were after, public-interest housing in the first case, heritage protection in the second.

Both municipal decisions came apart on two variables that any seller or buyer should check before signing, the moment the public authority moves and the price it offers. Nothing else was decided.

What is a Swiss pre-emption right?

A Swiss pre-emption right lets a holder named by contract or by statute take the buyer’s place in a sale that has already been signed. It sets no price of its own, it takes over the one the parties agreed, and that is precisely where the two Vaud municipalities were caught out.

Contractual or statutory, the distinction that matters

A contractual right comes from an agreement between private parties and, since the 1994 reform of rural land law, a pre-emption agreement over real estate is valid only in notarised form (art. 216 of the Code of Obligations). A statutory right comes from the law itself, under art. 681 and following of the Civil Code. It applies between co-owners, where the Federal Supreme Court held in ATF 73 II 165 that the conditions of art. 681 apply by analogy to the co-ownership pre-emption of art. 682, and a canton may also grant one to a public authority. A statutory right always ranks ahead of a contractual one over the same property.

Three months to act, two years at the outside

Art. 681a of the Civil Code requires the seller to tell the holder that a contract has been signed and what it contains. The holder then has three months to invoke the right, counted not from signature but from the moment the content of the contract was actually known, with an absolute limit of two years after the new owner is entered in the land register. The right stays enforceable against later owners, not against the first buyer alone.

Farm land follows rural land law

For agricultural property, federal rural land law adds a pre-emption right for the tenant farmer who already works the land and has economic control of it, and for close relatives of the seller over an agricultural business or holding. That right belongs before the ordinary civil courts rather than an agricultural authority (case-law summary).

Vaud sets the bar at 40 days and 1,500 m²

Vaud created its municipal pre-emption right with the law of 10 May 2016 on preserving and promoting the rental housing stock, the LPPPL. The right can be assigned to the canton and applies only in building zones of districts and municipalities hit by a housing shortage. Three conditions have to be met together.

• a public-interest housing project
• a location in a district or municipality in shortage
• a plot of at least 1,500 m², unless it sits inside a compact agglomeration perimeter or a recognised cantonal centre

The calendar is tight. The owner informs the municipality no later than the filing of the deed of sale with the land register, the municipality has 40 days to announce its purchase, and if it assigns the right to the canton, the canton gets 20 further days (Canton of Vaud). Sales between close relations, descendants, spouse, registered partner or cohabiting partner, fall outside the mechanism, as do properties in agricultural, wine-growing or forest zones.

What the authority gives back is heavy. On the usable floor area, 70 % must go to public-interest housing on an already built property, and 100 % when the authority does not build itself.

Le Mont-sur-Lausanne, the sale was already off

Two companies signed a promise of sale on 22 February 2023 and cancelled it themselves on 30 March 2023. The municipality still decided, on 4 April 2023, to exercise its pre-emption right over the plot.

The cantonal court quashed that decision on 14 December 2023 and the Federal Supreme Court confirmed it on 17 January 2025 (ruling 1C_56/2024). A cancellation made before the right is declared extinguishes the pre-emption case, by analogy with art. 216d of the Code of Obligations. The sellers had undone their own sale five days before the municipality moved, and the pre-emption went down with it.

Avenches, half the price does not work

The plot had been sold in 2013 through a repurchase arrangement, at 165 francs per square metre. In 2024 the municipality sought to exercise a cantonal statutory pre-emption right tied to heritage, separate from the LPPPL, and offered 3.4 million francs to buy the property back, roughly half the price the parties had actually agreed.

The cantonal court quashed the decision on 30 April 2025, and the Federal Supreme Court rejected the municipal appeal on 18 December 2025 (ruling 1C_300/2025). It is not arbitrary to find that a price covering half the contractual price does not match the agreed consideration.

Geneva allows 60 days, and only for public-interest housing

In Geneva the statutory pre-emption right sits in the general law on housing and tenant protection, the LGL, not in the LDTR. It serves the canton and the municipalities, solely to build public-interest housing, and in municipalities under 3,000 inhabitants the municipal right ranks ahead of the cantonal one.

The Council of State has 60 days to decide, and the right has to be noted in the land register. The Federal Supreme Court treats its use as a serious restriction of the property guarantee under art. 26 of the Constitution, which calls for strict review of the legal basis. Its case law has shifted on whether a concrete project is required, and ATF 142 I 76 remains the version most often cited.

What should a seller check before signing?

Two things, whether a pre-emption right is noted in the land register and whether a statutory case applies, the Vaud LPPPL or the Geneva LGL. A sale signed in ignorance of such a right holds at the time, yet it can be undone afterwards, and the deadlines are nothing alike.

• 40 days for a Vaud municipality
• 60 days for the Geneva Council of State
• three months for a federal civil pre-emption right, and up to two years after entry in the land register

The rest of what belongs in writing before signature, who pays what and on which date, has its place in the deed itself rather than in a verbal understanding between the parties.

For the buyer, a condition precedent beats a signature date

The buyer’s risk is a transaction neutralised after signature. The sale stays subject, for the whole statutory period, to the decision of the holder of the right, which argues for a condition precedent in the deed rather than trust in the date on it.

Read the other way round, the two Vaud rulings also say what an authority has to get right for its pre-emption to survive, act within its own deadline and offer the price the parties actually agreed. Otherwise the authority is the one that loses in court, and the seller keeps the buyer.

In brief

The Federal Statistical Office published its residential property price index for the third quarter of 2026 on 27 October 2026. The official index rose 1.7 % over the quarter and 4.4 % over a year, with single-family houses up 2.1 % on the quarter and owner-occupied flats up 1.3 %.

Those 4.4 % over twelve months are also the real story in Avenches. A property bought in 2013 cannot be bought back at the 2013 price, which is what the Federal Supreme Court told the municipality.