Union Investment Signs 9,666-Sqm Office Lease at Düsseldorf's Seestern 3, Cushman & Wakefield Brokers Deal

Union Investment Real Estate Real Estate has signed a 10-year lease agreement for approximately 10,000 sqm at Seestern 3, a LEED Gold-certified office building in Düsseldorf's Seestern district, the firm announced Aug. 10, 2026. Cushman & Wakefield acted as broker on the transaction, which leaves the property fully leased.

Deal Details: Tenant, Space, and Timeline

A global technology group has secured 9,666 sqm of office space, 179 sqm of storage space, and 140 parking spaces at Seestern 3. The lease term is 10 years, with occupancy set to begin in the second quarter of 2027. RKW Architektur is handling tenant fit-out planning for the incoming occupier. The property, which carries a total leasable area of approximately 33,000 sqm across five stories, is now fully leased.

About Seestern 3 and Its Place in the UniImmo: Europa Portfolio

Seestern 3 has been part of Union Investment's UniImmo: Europa open-ended real estate fund since 1999. The building was designed in 1961 by Düsseldorf architect Helmut Rhode for the headquarters of the Horten department store group and holds a notable place in German architectural history as the first building in the country constructed exclusively as an open-plan office.

Union Investment undertook an extensive modernization of the property between 2013 and 2015. The building subsequently achieved LEED Gold certification and is a designated historic landmark. The property features its own park, two inner courtyards, a three-story pavilion, and a terrace facing the park.

Seestern District: An Established Office Submarket

Seestern 3 is located in the Seestern office district on the left bank of the Rhine in Düsseldorf. The submarket has established itself as a hub for media and communications technology companies and is characterized by strong infrastructure, multiple hotels, and corporate headquarters.

Market Context: Flight to Quality in Office

The lease at Seestern 3 reflects a broader pattern in office markets, where tenant demand has gravitated toward well-located, high-quality buildings with strong ESG credentials. Office vacancy has remained elevated across many markets in recent years, but assets with differentiated positioning — including historic buildings that have been modernized to contemporary standards — have continued to attract long-term commitments. Tenant demand has increasingly concentrated in modernized, amenity-rich buildings, which helps explain why a renovated landmark like Seestern 3 can secure a decade-long commitment from a global technology occupier.

For Union Investment Real Estate, the 10-year lease secures a long-duration income stream for a core asset that has been held in the UniImmo: Europa portfolio for more than two decades.

Sources

Union Investment Real Estate — Press Release: Union Investment leases approximately 10,000 sqm in the well-known Düsseldorf office building "Seestern 3"