Medallion Signature Guarantees

A medallion signature guarantee, similar to a Notary Stamp, is a warranty by a signature guarantor that the endorser is an appropriate person to endorse and transfer a security instrument to another party. Medallion signature guarantees are widely used across the securities investment industry to protect shareholder accounts and prevent the unauthorized transfer of securities. A guarantee of a person’s signature is required by a transfer agent before a securities transfer can take place. Any sale or transfer of securities requires an endorsement by the holder much like cashing a check and subsequently, every endorsement requires a signature guarantee by an acceptable and/or recognized Guarantor, such as a bank, broker or other financial institution that has been certified to issue medallion signature guarantees. The actual medallion signature guarantee is a special imprint (stamp) that uses a green high security ink (specimen displayed to the right).

Specimen Medallion Signature Guarantee
(Specimen Medallion Signature Guarantee)

Medallion Signature Guarantee Uses

A medallion stamp can be used to guarantee proper endorsement on the following transactions:

  • Stocks
  • Warrants and other Securities
  • Bonds and Savings Bonds
  • Mutual Funds
  • Unit Investment Trusts

Where to Get Your Medallion Guarantee

Securities and Exchange Commission (SEC) regulations determine which types of financial institutions are eligible to provide medallion guarantees:

  • Domestic Banks
  • Trust companies
  • Credit Unions
  • Broker dealers
  • Clearing agencies
  • National securities exchanges
  • Savings associations (including Savings and Loan associations)
  • Municipal securities broker/dealers
  • Registered securities associations
  • Government securities broker/dealers whose net capital exceeds $100,000

Search for a Medallion Guarantor

Instructions to Obtain a Medallion Signature Guarantee

Shareholders can obtain medallion signature guarantees from banks, credit unions and brokerages. Most banks and credit unions require the requesting individual to hold an account in good standing and may ask for the following:

  1. 1. Your account number
  2. 2. You will usually need two forms of ID. Your current, non-expired government issued identification. If there is more than one account owner, all owners must be present at the same time and show current, non-expired government issued identification.
  3. 3. Your original stock certificate or the most recent account statement showing ownership, account number and value of the security
  4. 4. Proof that you are the authorized signor as:
    • Trustee
    • Executor
    • Power of Attorney
    • Beneficiary to sign in a capacity other than owner (if you are not the owner of the security). This may include Trust Agreements, Power of Attorney documents, Death certificate and Corporate Resolution.

Please note: Your bank may decline or refuse to provide a medallion signature guarantee if the documentation and/or the forms provided are insufficient to determine the appropriate person to sign.

Foreign Guarantors

Kemark Financial Services, administrator of the STAMP program, has accepted three guarantors located in the United Kingdom into the program. These guarantors will provide Medallions for foreign investors at a fee, even if they reside in a country other than the U.K. Here is a list of the foreign guarantors:

Not a Notary Stamp

Signature Guarantee Programs have been developed and eligible financial institutions which subscribe to such programs are issued Medallion Guarantee Stamps. Transfer agents are obligated to ensure that such stamps appear on the transfer documents and are entitled to refuse a transfer of shares if a signature is not guaranteed with a stamp. A notary stamp is not acceptable when transferring the ownership of stock.

How to Become a Medallion Signature Guarantor

Kemark Financial Services, is the STAMP Program administrator who operates the official signature guarantee program that is recognized and approved by the financial industry and that is supported by the Securities Transfer Association (STA). Transfer agents pay a yearly subscription fee to Kemark and lease their bar code scanner and a special ink reader. The document reader verifies that the specific financial institution is still assigned to that particular stamp, and that the stamp is still valid. If the stamp is read as “Lost” or “Destroyed”, the transfer agent is not protected and must reject the item or be willing to accept the liability for accepting an invalid Medallion Signature Guarantee.

Any financial institution wishing to become a recognized signature guarantor must apply by filling out the STAMP application forms from Kemark Financial Services, Inc., which include the subscription and indemnity agreement. It must also contact their insurance company to execute a Surety Bond form. Kemark’s fee is approximately $495 which covers the first 13 months, with an annual fee after that. The Guarantor must also receive certification through training.

Once the institution has completed the registration requirements and has been accepted by Kemark they will be provided with a STAMP2000 Medallion stamp. The stamp uses high-security green ink and requires a STAMP2000 Transfer Agent Document Reader to be used by the transfer agent to authenticate the Medallion imprint.


The Uniform Commercial Code provides that a person guaranteeing a signature warrants that at the time of signing:

  • The signature was genuine;
  • The signer had legal capacity to sign; and
  • The signer was a appropriate person to endorse the security

If a registered owner is wrongfully changed due to an improper guarantee, the guarantor or its insurance will be required to compensate the transfer agent and/or issuer for any losses.


Guarantors must understand the importance of providing proper medallion signature guarantees. Here is a list of several safeguards that can protect the guarantor:

  • Signature guarantees should be provided to customers only
  • Verify proper identification
  • Verify signature with signature card on file
  • Require in person signatures
  • Verify that the signor is of legal age and competent to sign
  • Verify that the signor is authorized to endorse the security
  • View and verify that the security certificate exists with a statement or the certificate itself
  • Do not provide a guarantee on a blank stock power
  • Do not provide a guarantee unless all owners are physically present and sign in your presence
  • Always make and retain copies of each signature guarantee and supporting documents

Behind the Medallion Signature Guarantee Program

Over 6,000 banks, credit unions, brokerage firms and financial institutions belong to the medallion signature guarantee program. Financial institutions are recognized by the Securities Transfer Association by becoming a member of one of the three recognized medallion signature guarantee programs:

  1. STAMP (Securities Transfer Agents Medallion Program): Participants include transfer agents, broker dealers, clearing firms and other financial institutions.
  2. SEMP (Stock Exchanges Medallion Program): Participants include regional stock exchange member firms, and clearing and trust companies.
  3. MSP (New York Stock Exchange Medallion Signature Program): Participants include NYSE member firms.

Transfer agents and others who rely upon signature guarantees from a member of one of the 3 above-mentioned programs are protected against loss from wrongful endorsements if the Guarantor is unwilling or unable to meet its financial obligation under its Program Indemnity Agreement. Joining the STAMP Program requires the Guarantor to purchase the necessary imprinting equipment with special ink and to obtain Surety Bond coverage. An original STAMP Medallion Signature Guarantee uses bar codes and special ink to deter counterfeiting. For this reason, only originals can be accepted. Please note: A notary’s seal cannot substitute for a medallion signature guarantee. Medallion signature guarantees must validate the genuineness of the person signing the document as well as the authority and capacity of the person signing the document. Transfer agents can refuse to accept a signature guarantee if it is not enrolled in the Medallion program or it is not recognized by the transfer agent. The Uniform Commercial Code (UCC) entitles transfer agents to use the Medallion program to protect the transfer agent and issuer against fraudulent and unauthorized stock transfers.

Medallion Coverage Limits

Medallion signature guarantees must cover the full amount of the security that is being transferred. There are several different coverage levels, therefore it is important to acquire a guarantee amount equal to or greater than the amount of the transaction.

Each medallion signature guarantee has a unique identification number with a letter prefix signifying the dollar amount insured by the Guarantor. Each prefix with the corresponding amount of coverage is listed below:

  1. A: $1,000,000
  2. B: $750,000
  3. C: $500,000
  4. D: $250,000
  5. E: $100,000
  6. F: $100,000 (Credit Unions-per transaction)
  7. X: $2,000,000
  8. Y: $5,000,000
  9. Z: $10,000,000

In addition, any transfer agent who is a member of the Securities Transfer Association receives $4,000,000.00 insurance against stolen or counterfeit medallion stamps.