Authentication of the document basically means that an official, usually called a notary, certifies that the document was signed by a specific person. The notary identifies the person signing the document and attaches a notary seal with notarized deed to the document. In this way, any third party can be sure that the signature of the document is real and not forged. This service is called a notarized signature. However, you must be aware of the risk that the signing party does not know the contents of the document.

Although notarization can make a document fully legal and recognizable, notarization may be insufficient to be recognized in other states. This happens because each jurisdiction recognizes its own public authority and not that of other states. In cases where a document needs to be notarized to be used in another jurisdiction, an apostille certificate can be helpful and make the document valid abroad.