The same signature on two documents: what actually matches?

Legal document examination / Research and articles

Hypothetical example. Two payment instructions show different amounts, yet the last loop of each signature stops at the same point beside the same tiny speck. Two files identical byte for byte are duplicate files. With different amounts, compare the entire pages before isolating the repeated region. A close match around the signatures raises the possibility that both versions used the same image.

Keep the files as received and the messages that carried them. An examiner also looks beyond the signature, for instance at a form line broken in the same place, and asks for source files, any paper originals and known signatures. Authorized and unauthorized reuse can look identical. The overlap alone cannot establish which document came first, who inserted the image, consent or fraud.

Professional source · nvlpubs.nist.gov