俺负责地告诉你，店主不用负责。

In cases of credit card theft, a suit against a store will inevitably fail. The reason is simple. The store is under no legal obligation to check signatures, and is not the party that caused your card to be stolen. Consequently, suits against the store -- unless the store has broken the law by giving your card information to a third party or not properly securing your information -- will be unsuccessful, and could even cause the judge to award attorney's fees or court costs to the store.

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