I am signing my card with a big CID which means the provider must ask the bearer of that card for a valid ID to prove who he is. If a person signs my name over that CID it means nothing. Call your CC company and ask. In the case of Citicard my signature is imbeded in the front of my card right under my photograph. Not to many people are as ugly as me but if they are lucky enough to have the same mug as me as well as the same drivers license then they might be able to use my card.
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