Max von Mandl-Maldenau (3 August 1865 – 6 August 1942) was an Austrian entrepreneur and art collector.

Born on 3 August 1865 in Prostějov, Moravia, Austrian Empire, Max Mandl-Maldenau managed branches of a weaving mill and leather wholesaler in Vienna and Königinhof an der Elbe (now Dvůr Králové nad Labem, Czech Republic). He married Elsa and lived in Vienna on Kochgasse 14 which contained valuable furnishings ^[1].

The Mandl-Maldenau art collection included paintings by Old Masters such as Jan van Eyck, Jacob van Ruisdael, and Jacopo da Ponte-Bassano. When Austria merged with Nazi Germany in the Anschluss of 1938, they were forced to flee the Nazis. Their firm was Aryanized.^[2] The art collection was acquired by Nazi dealer Friedrich Welz. Elsa fled to France, where she died in 1939, while Max escaped to Portugal and died on 6 August 1942 in Lisbon.^[3]

In 1953, their son-in-law Richard L. Winton-Wiener searched unsuccessfully for the collection at institutions like Dorotheum and Galerie Welz. In 1962, their children filed claims with the Fonds zur Abgeltung von Vermögensverlusten [de]. In 1966, they received some compensation for seized properties. Following research under the 1998 Art Restitution Act, and a recommendation by the Austrian panel in 2009,^[4] the Österreichische Galerie returned Johann Peter Krafft's Male Portrait in 2011.^[3]

The Mandl-Mandenau heirs have registered search request for five artworks that were seized under the Nazis on the German Lost Art Foundation Database.^[5] These include The Monk painted by Ferdinand Georg Waldmüller in 1841^[6]and The Blind Cow Game, painted by Peter Fendi.^[7]