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What is the difference
between legalization and apostille?
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Legalizing (also called attestation) a document is something only a non-Hague Convention member foreign consulate or embassy can issue on a legal document that is presented to them.
Apostilling a document is something only one of the 50 U.S. Secretary of state offices or the U.S. Department of State can issue on a legal document presented to them for a country that is a part of The 1961 Hague Convention Treaty.