These two details of the back of Untitled [glossy black painting] show staples and drips of black, pink, and red-orange paint along the work’s tacking margin, the section of canvas that wraps around its wooden stretcher and is secured to the back. The colored paint reveals that this painting was made on top of an unknown work by Rauschenberg or another artist. Always short on money and supplies in the early 1950s, Rauschenberg is known to have painted over both his own works and the castoffs of fellow artists. In the detail on the left, pink paint covers black drips, suggesting that the earlier painting also included black.