Well the Andy Warhol Supreme Court case should have a decision soon. The argument I find compelling in support of Warhol is that his painting is fair use and th

Well the Andy Warhol Supreme Court case should have a decision soon. The argument I find compelling in support of Warhol is that his painting is fair use and that it “meaningfully transformed” the source material (photo of Prince). It is an appropriation, not a copy. In your example I’d say that Lichtenstein meaningfully transformed the source material and is fair use of a drawing in a book of drawings. But making t-shirts of either the source or the painting would not meaningfully transform it nor would it be fair use and therefore a copyright violation.