Martin Kippenberger's *This work is unique.* presents a sardonic meditation on authenticity and mass reproduction, using photo-offset postcards — inherently multiple and commercial objects — as the ground for mixed media intervention. By declaring uniqueness across what are fundamentally reproducible printed surfaces, Kippenberger exposes the contradictions embedded in art world value systems and the myth of the singular masterpiece. The artist's frame further asserts authorial control, transforming disposable ephemera into a deliberately framed institutional statement dripping with his signature irony.