Shareholders who own stock may either have their shares held electronically by their brokerage firm or they may hold paper stock certificates. If stock certificates are ever lost, stolen, or destroyed, they can be replaced. The requirements to have share certificates replaced vary from corporation to corporation. Fortunately, the general procedures are the same and can typically be accomplished with minimal research.
Contact the investor relations department of the company you own shares of stock in. The investor relations department may be able to help you directly with the process of replacing your lost stock certificates. If not, they can tell you who can help. Companies typically use a transfer agent to handle the actual process of registering and providing shares of stock. In that case, the transfer agent will likely handle replacing stock certificates.
Contact the transfer agent that handles shares for the company and tell them to place a "stop" on the missing certificates. A stop works much like stopping payment on a check. Once the stop has been placed, no one can transfer or sell the shares assigned to the missing certificates.
Request a new certificate immediately. The owner of a lost stock certificate must request a new one before an "innocent purchaser" acquires the old certificate, otherwise the claim cannot be processed.
Buy an indemnity bond if required. Some transfer agents require you to purchase an indemnity bond to protect them in the event that an innocent purchaser later presents the lost certificate to be redeemed.