In the United States, a Medallion signature guarantee can be obtained from a bank, credit union or financial institution that is part of the Securities Transfer Association Medallion Program or the NYSE Medallion Signature Program. A notary public cannot provide this service.
A Medallion signature guarantee is used to sell or transfer securities. The medallion is a guarantee of the authenticity of the document's signature and limits the transfer agent's liability in the event a signature is found to be fraudulent. Liability is assumed by the institution that guaranteed the signature by affixing the Medallion stamp.
Large or small, local or national, many banks offer Medallion signature guarantee. More than 7,000 banking and financial institutions participate in the Medallion program. When a Medallion signature guarantee is required, a guarantee of signature will not be accepted from institutions that do not participate in the Medallion program.
Outside the United States, a U.S, embassy can provide a signature guarantee in the form of a consular seal. Military personnel stationed outside the U.S. may attest to the authenticity of their signature by appearing before an authorized adjutant or legal officer.
To obtain a Medallion signature guarantee, the amount of the transaction must not exceed the amount of the surety covered by the Medallion.