DEFINITION of 'Medallion Signature Guarantee'
One of several special certification stamps which guarantee that the signature authorizing the transfer of securities is authentic. A Medallion signature guarantee is commonly required when an owner wants to sell or transfer securities, such as stocks or bonds, which are held in physical certificate form. If you hold securities through a broker, you will not need to get a signature guarantee to sell or transfer the securities.
BREAKING DOWN 'Medallion Signature Guarantee'
In order to provide a Medallion signature guarantee, an institution must be a member of one of three Medallion signature guarantee programs: the Securities Transfer Agents Medallion program, the Stock Exchanges Medallion Program and the New York Stock Exchange Medallion Signature Program. Normally, you can obtain a Medallion signature guarantee at a financial institution where you are already a customer. A small charge may be assessed for this service by your bank.