Warhol created this set of four mimeograph stencils in response to a request from the Pasadena Art Museum for works that could be reproduced and sold in conjunction with a 1962 group exhibition. He drew directly on the blue paper with a stylus that made perforations through which ink could be forced to produce copies. His images represent several of his key subjects at the time, including a Campbell's soup can.
The mimeograph, which was replaced by the photocopy later in the 1960s, was a low-cost means of making copies. This is the only known occasion when Warhol used it to make artworks. It seems these sheets were never actually used to make copies.
from Andy Warhol: Campbell's Soup Cans and Other Works, 1953–1967, April 25–October 18, 2015