An Affidavit of Loss of Stock Certificate is a written statement under oath where a person (the “affiant”) declares the physical loss of a certain stock certificate. In short, it means the stock certificate is lost and can no longer be found. The loss can be due to inadvertent misplacement, theft, destruction by fire, flood or other means.
In practice, an authorized officer of the corporation executes the Affidavit of Loss of Stock Certificate (e.g. its corporate secretary).