Yes, the medallion stamp that operators possess has a maximum surety value assigned, which means some shareholders with higher value holdings may struggle to find a medallion service provider outside the US and Canada.
 

Stamps have a prefix that indicates their surety limit, which limits how much they can guarantee the transaction for:

 

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

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

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