1. A computer-implemented system for preventing overlap during the application of a universal identifier to a signature document in an electronic signature service comprising: a means for parsing an image file of the signature document to obtain a content vector, wherein a set of addresses of the content vector uniquely correspond with a set of locations in the image, wherein at least one value in the content vector indicates unexecuted signature document content, and wherein each value in the content vector indicates content at a corresponding location in the image; a means for measuring an overlap quantity for a potential universal identifier location, wherein the means for measuring uses the content vector to measure the overlap quantity; a means for selecting a universal identifier location in the signature document, wherein the means for selecting uses the overlap quantity; and a means for applying the universal identifier to the signature document, wherein the means for applying uses the universal identifier location.