 In October 1997, Rosenberg's heirs filed suit in United States District Court for the Western District of Washington, Seattle, to recover the painting "Odalisque" (1927 or 1928) by Matisse from the Seattle Art Museum, the first lawsuit against an American museum concerning ownership of art looted by Nazis during World War II.Then museum director Mimi Gardner Gates brokered an 11th hour settlement that returned the artwork, after which the museum sued the gallery which had sold it the painting in the 1950s.As the sole heir to her parents' estate, after the death of her mother Micheline in 2007, Sinclair sold the painting at auction, raising in excess of $33m.