File:Photo of Interchanged by Willem de Kooning.jpg

Licensing
Publication occurred in 1955, when the painting was offered for sale at the Sidney Janis Art Gallery in New York. No copyright renewal found in the U.S. Copyright Catalog. Furthermore, the work appears to have never been copyrighted. No copyright notice is apparent in photographs of the painting, and no registration is found in the 1955 or 1956 copyright catalogs.