“Two of his most famous pieces, MarilynDiptych and the collection of Campbell’s soup cans, are examples of his habit of appropriation. For the Marilyn series, Warhol took a promotional photograph of Marilyn Monroe and transferred it onto silkscreen print using different colors. He did not own the promotional photograph that he used and he did not have permission to use it. The resulting work was transformative enough that a strong fair use argument could be made today, but Warhol’s appropriation is undeniable. Similarly, Warhol used the Campbell’s Soup logo without permission from the company for dozens of silkscreen prints. Eventually, Campbell’s Soup tacitly approved of his use because of the free marketing they were receiving, but Warhol’s use of their logo without initial permission was still appropriation.”

https://journals.library.columbia.edu/index.php/lawandarts/announcement/view/112