Vonovia's Berlin Exposure Back in the Spotlight as Giffey Picks Apart Expropriation Math

Franziska Giffey, Berlin's still-serving economics senator, has issued a blunt warning about the city's plans to socialise large private housing portfolios, arguing that the compensation budget on the table is unrealistic and that the whole project risks years of litigation and a freeze in new construction. Her intervention lands squarely on Vonovia, the capital's biggest private landlord and the company most exposed to the scheme.

The DAX-listed group holds close to 140,000 units in Berlin together with its subsidiary Deutsche Wohnen — a slice of a total portfolio exceeding 570,000 apartments. Under the framework agreed by the SPD, Greens and Left party during exploratory talks, private landlords owning more than 10,000 Berlin flats would be targeted, with new builds completed after 1 January 2021 and a floor of 10,000 units per company carved out. On paper, as many as 120,000 Vonovia apartments could fall within scope. The citywide push covers roughly 160,000 homes in all, drawing in portfolios held by Heimstaden, Adler and Covivio as well.

A 16 Billion Euro Cap Against a 40 Billion Euro Bill

Money is the fault line. The exploratory paper sets a compensation ceiling of EUR 16 billion, which works out at about EUR 100,000 per apartment across the 160,000 units in question. Berlin's own court of audit estimated in 2024 that paying fair market value could cost as much as EUR 40 billion. The city already carries liabilities of just under EUR 70 billion.

Independent calculations sketch a narrower range. The German Institute for Economic Research (DIW) puts compensation for 160,000 flats at EUR 14.4 billion. Keeping rents at the targeted level would, by the DIW's reckoning, require annual state subsidies of EUR 366 million on a compensation volume of EUR 15.12 billion.

Legal Path Is Untested Territory

Even the timetable is drawn out. A draft law is not expected before mid-2028, with a constitutional review likely to follow. The Berlin House of Representatives is slated to pass the legislation in 2028, meaning any transfer of ownership would come no earlier than 2029. An expert commission concluded in 2023 that socialisation under Article 15 of the German constitution was feasible in principle, but left the central questions of proportionality and compensation levels unanswered — and Article 15 valuation remains legally uncharted, pointing to years of proceedings before the Federal Constitutional Court.

Giffey's concern is that affected groups may halt pending investment and new-build projects while the uncertainty drags on, tightening an already strained supply of housing.

The Market's Verdict

Investors have been pricing in the political risk for months. Vonovia shares closed Friday at EUR 16.73, down 32% since the start of the year and just 3.5% above the 52-week low of EUR 16.18 touched on 8 October. The stock changes hands at a discount of roughly 60% to reported book value, leaving the group with a market capitalisation of EUR 13.85 billion.

Two forces are pressing on the valuation: a higher interest-rate environment that has raised financing costs, delayed projects across the sector and worsened the housing shortage in German conurbations, and the persistent political debate over Berlin's housing stock.

Not everyone is bearish. Jefferies rates the shares a buy, and JPMorgan also carries a positive recommendation, with parts of the analyst community arguing the Berlin risk is largely reflected in the price. Whether that gap to net asset value narrows depends on where rates go next — and on whether the capital's plans survive their date with the constitutional court.