Authentication
Korean Signature & Private-Document Authentication (사서증서 인증)
Signature authentication (사서증서 인증) is a notarial act in which a notary confirms that a signature on a privately prepared document is genuine — that the named person really signed it. Foreign parties often require this for letters, declarations, and forms that are not government-issued. Find an agent on Seoul Apostille who arranges the notarial authentication and, for overseas use, the Ministry of Justice apostille, so the signed document holds up abroad.
When This Service Is Relevant
- A foreign party needs proof that you personally signed a letter or form
- Authenticating a declaration, undertaking, or consent that you prepared
- Confirming a signature on an application or form a foreign authority requires
- Verifying signatures on a private agreement before sending it abroad
- Any privately prepared document a foreign party will only accept if signature-verified
What to Prepare
- The document to be signed, or already signed (do not sign in advance if the notary must witness it)
- Your ID or passport
- The party and country that will receive the document
- Any form or wording the receiving party requires
Process Notes
- The signer normally appears before the notary, who verifies identity and that the signature is genuine — sometimes you must sign in front of the notary.
- Authentication (인증) of a private document differs from a notarial deed (공정증서); your agent uses the form the receiving party needs.
- For overseas use, the authenticated document is apostilled by the Ministry of Justice (법무부); your agent handles this step.
- Confirm the receiving party's required wording before authentication to avoid having to redo it.
Frequently Asked Questions
What does signature authentication actually certify?
It certifies that the signature on a privately prepared document is genuine — that you really signed it. It does not vouch for the document's contents, only the signature, which is what many foreign parties require.
Should I sign the document before coming in?
Sometimes the notary must witness the signing, so it is best not to sign in advance until your agent confirms the requirement. Tell your agent the receiving party's instructions and they will advise.
Do I need an apostille as well?
For overseas use, yes. After the notarial authentication, the Ministry of Justice apostilles the document. Your agent handles both steps and any certified translation.
How is this different from notarizing a contract?
Signature authentication (인증) confirms a signature on a private document, while a notarial deed (공정증서) is a document the notary draws up with stronger effects. Your agent uses whichever form the receiving party accepts.
Related Documents
Need This Document Authenticated?
Share your document and the requesting authority. We'll connect you with an agent who coordinates authentication and any required follow-on steps.