Mario Leißner

A prior longstanding General Counsel of the leading German institutional real estate fund sponsor, Sal. Oppenheim Immobilien-Kapitalanlagegesellschaft mbH, Mario Leissner was founder of the German offices of King & Spalding LLP, a leading global law firm, in 2007. For 15 years, i.e. from the opening of the office until his retirement from the operative professional career effective July 1, 2022, Mario served as German Managing Partner and headed King & Spalding’s German Investment Funds and Real Estate Capital Markets practices. Mario also was a member of the firm’s International Strategy Committee.

With 27+ years of experience, Mario specialized in fund structuring, regulatory and investment law, and international and German real estate transactions. His award-winning practice also involved corporate and financing work as well as litigation and international taxation.

Over the last years, Mario constantly has been recognized by Chambers, Legal 500, JUVE, and other business law publications as a leader in both investment funds law and real estate law. immobilienmanager named him, as one of only four lawyers, to its „Walk of Fame“, the list of the 100 leading and most influential „heads“ of the German real estate industry.
According to Handelsblatt in cooperation with „Best Lawyers“, Mario is one of Germany’s 2016, 2017, 2018, 2019, 2020, 2021, and 2022 best lawyers. Who’s Who Legal also lists him among Germany’s best lawyers. In 2014 and 2019, his practice was the only law firm practice ever to win the renowned immobilienmanager Award, given by the real estate industry – and it won the price twice which is unique for this award. Additionally, Mario’s practice has been nominated two consecutive times for the Real Estate Law Firm of the Year JUVE Award.

Mario has been representing:
• the vast majority of the German capital investment companies (KVG), a variety of major international investment fund managers (AIFM), open-ended and closed-ended investment funds (AIF), international and German asset managers, institutional real estate investors, and custodians in their legal and regulatory structuring and in all aspects of their worldwide acquisitions, financings, and sales as well as major litigations;
• non-German/non-European investors in their inbound investments in German/European real estate.

Mario Leissner has conducted more than 2,500 transactions worldwide with an aggregate value in excess of US$ 200 billion.

A frequent speaker and author, Mario is fluent in German, English, and French, proficient in Russian and also speaks Spanish and Italian.

Publications / Lecturer Engagements

• Co-Author “Rechtshandbuch Immobilien-Investitionen” (C.H. Beck)
• Co-Author “Business Laws of Germany” (West/Thomson Reuters)
• Co-Author and Strategic Partner “Deutscher AnwaltSpiegel” (F.A.Z.-Institut)
• Lecturer for Management Circle AG
• Lecturer for Euroforum Deutschland GmbH
• Lecturer for Chambers of Commerce and Chambers of Trade
• Frequently speaks to industry groups on regulatory, fund and real estate law as well as on transaction matters

Language Skills

• German (mother tongue)
• English (business fluent)
• French (business fluent)
• Russian (fluent)
• Italian (conversant)
• Spanish (conversant)