Much recent discussion has focused on the nature of artifacts, particularly on whether they have essences. While it is often held that artifacts are intention-dependent and necessarily have functions, it is equally commonly held, though far less discussed, that artifacts are the result of physical modification of some material objects. This paper argues that the physical modification condition on artifacts is false. First, it formulates the physical modification condition perspicuously for the first time. Second, it offers counterexamples to this condition, both concrete and abstract. Third, it considers, and rejects, two responses to these counterexamples, one which appeals to the distinction between being a K and being used as a K and ano...