Mona Lisa
The painting is thought to be a portrait of Lisa Gherardini, the wife of Francesco del Giocondo, and is in oil on a white Lombardy poplar panel. It had been believed to have been painted between 1503 and 1506; however, Leonardo may have continued working on it as late as 1517. Recent academic work suggests that it would not have been started before 1513. It was acquired by King Francis I of France and is now the property of the French Republic, on permanent display at the Louvre Museum in Paris since 1797.
Ronald Lauder
On June 18, 2006, he purchased from Maria Altmann and her family, the painting "Portrait of Adele Bloch-Bauer I" by Gustav Klimt for $135 million, the highest price ever paid for a painting at that time. Lauder called the painting "Our Mona Lisa". He reportedly saw Klimt's portrait as a youth in Vienna and had admired it since. The painting, a Nazi-looted art piece which had just been restored to Altmann following years of negotiation and litigation with the Austrian government, now forms the centerpiece of the museum's collection.