Signature guarantees and notary stamps are both used to verify signers’ identity. Loan documents, for instance, require professional notarization to protect against fraud. The notary public verifies the signer’s identify – usually done by checking his or her driver’s license of state-issued ID card – and stamps the document to finalize its execution. While a signature guarantee shares some similarities to a notary stamp, they are two unique processes, each with its own purpose.