A certificate attached to a notarial certificate (which is attached to a legal document such as a power of attorney or contract) or a public document (for example, a birth or marriage certificate) which certifies the:
Authenticity of the signature on the notarial certificate or public document.
Capacity in which the person (the notary or public official) signing the document acted.
Identity of any stamp or seal affixed to the document.
Before a legal document issued in one country can be recognized in another country, that document must be legalized or authenticated. For countries that are signatories to the 1961 Hague Convention Abolishing the Requirement of Legalization for Foreign Public Documents (the Hague Convention), this legalization process has been simplified. Under the Hague Convention, signatory countries have agreed to recognize public documents (including notarial certificates) issued by other signatory countries if those documents are apostilled.
For non-signatories, legalization of documents is more complicated and requires that the document be authenticated by a consular official.
To obtain an apostille in the US for an agreement, the agreement must be notarized and submitted to the Secretary of State of the state where the notary is authorized. The Secretary of State authenticates the signature of the notary and the seal on the notarial certificate and signs the apostille certificate. The party seeking the apostille and notarial flag must pay the Secretary of State and county clerk their required fees. For more information on the apostille process, see Hague Convention on Private International Law: Apostille Section and US Dept. of State: Apostille Requirements.
As of July 2012, there are 104 signatories to the Hague Convention including the US and UK.
For a form of the apostille certificate, see Form of apostille certificate annexed to the Hague Convention of 1961 Abolishing the Requirement of Legalisation for Foreign Public Documents ( www.practicallaw.com/4-382-2828) .