This excerpt taken from the HSY DEF 14A filed Mar 16, 2007.
What does it mean if I received more than one proxy card?
You probably have multiple accounts with us and/or brokers, banks or other nominees. You should vote all of the shares represented by these proxy cards. Certain brokers, banks and nominees have procedures in place to discontinue duplicate mailings upon a stockholders request. You should contact your broker, bank or nominee for more information. Additionally, our transfer agent, Mellon Investor Services LLC, can assist you if you want to consolidate multiple registered accounts existing in your name. To contact our transfer agent, write to Mellon Investor Services LLC, 480 Washington Blvd., Jersey City, NJ 07310, or call: