In a Wednesday announcement, the Academy cites Leonardo DiCaprio as the primary benefactor.
"Leo's passionate leadership has helped us bring home this legendary piece of movie history," said Academy CEO Dawn Hudson. "It's a wonderful gift to the Academy museum project, and a perfect representation of the work we do year-round to preserve and share our film heritage."
Walt Disney CEO and chair of the capital campaign for the Academy Museum of Motion Pictures Bob Iger echoed Hudson's sentiments. "The ruby slippers occupy an extraordinary place in the hearts of movie audiences the world over," he said. "This is a transformative acquisition for our collection."
DiCaprio led the group of donors that enabled the purchase, which was brokered by auction house Profiles in History. Steven Spielberg and LACMA co-char Terry Semel were also among those involved.
These particular slippers, which many think were worn by Garland during close-ups, insert shots and the famous heel-clicks back to Kansas, bounced private collections, including costumer Kent Warner's, after being stored in MGM's Culver City lot for the three decades following Oz's production.
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Rhys Thomas, author of The Ruby Slippers of Oz, called them "the holy grail of all Hollywood Memorabilia" in a statement from the auction house. "Of the four pairs of authentic ruby slippers known to exist, this pair offered by Profiles in History, marked '#7 Judy Garland' and known as the 'Witch's Shoes,' are the most important and most valuable," he added.
They are expected to go on display at the Academy Museum of Motion Pictures when it eventually takes residency in Wilshire's May Company building.