American Express is strongly committed to the security of all our Cardmembers ’ information and wants to inform you that a merchant where you have used your American Express Card for payment detected unauthorized access to their website . At this time , we believe the merchant ’s affected data files included your American Express Card account number , your name and the expiration date on your card . Importantly , your Social Security number is not impacted and our systems do not show any indication of unauthorized activity on your Card account related to this incident . ;