The 79-inch-by-69-inch canvas was painted in 1975 and acquired by Allen in 2001 for an undisclosed sum. De Kooning’s paintings from this period are especially sought after and considered the most desirable of the artist’s oeuvre, according to a statement by the Lévy Gorvy Gallery, based in New York and London, who is selling the work.

The highest amount ever paid at auction for a de Kooning was $66.3 million for the 1977 Untitled XXV sold to an anonymous bidder at Christie’s in 2016. After the ’70s, de Kooning’s value seemed to have declined. A 1982 work Untitled XIX, part of the Peggy and David Rockefeller Estate up for sale at Christie’s in May 2018, has an estimate of $4 million to $6 million.

It’s not clear why Allen has decided to part with such an unusually fine painting. Alexa Rudin, spokesman at Vulcan, Inc., Allen’s family office that manages his business and charitable interests and whose staff includes 15 art experts, said in an email: “The sale is a normal course of business for a collector like Paul Allen.”

“For collectors at that level, we know they aren’t deaccessioning for financial reasons but for emotional or aesthetic ones,” said Dominique Lévy, co-founder of the Lévy Gorvy Gallery. “I find that exciting because it means that the collection is alive. It shows the development of being a collector in the arts when things are in movement.”

Untitled XII was painted at a key moment in the artist’s life, when de Kooning was moving away from figurative representation toward abstraction, and Untitled XII showcases his maturity and dexterity with color and form, according to Lévy.

Lévy says Hong Kong was chosen to present the painting because he believes Asian collectors respond well to de Kooning’s style.

“De Kooning has a dialogue with Asian sensibility that is quite strong, whether it is coming from the interest in Asia in calligraphy, or the brushstroke or the movement and the relationship to landscape,” Lévy says. “They understand it.”

Part of the reason for the excitement around the sale of Untitled XII is that in the arc of de Kooning’s life—he eventually succumbed to Alzheimer's disease at age 92—the 1970s was a period of extraordinary vitality.