WHEN IS THE MEDALLION SIGNATURE GUARANTEE REQUIRED?
If your investments are held by a US or Canadian transfer agent or custodian, you will require the stamp to:
Transfer assets to another person or entity.
Transfer assets to a beneficiary upon the death of a shareholder.
Correct an registration details - change of address or change of name, such as from maiden to married name;
Corporate Actions e.g. exchanging old shares for new after a takeover or merger.