Abstract: A system for processing coupons includes a coupon scanner for reading information from a coupon and a host processor for using the information to determine whether the coupon is valid. The coupon scanner includes a coupon modification unit for use in modifying valid coupons so that the coupons are no longer redeemable. The coupon scanner also includes a coupon sorter for sorting valid coupons between the coupon modification unit and an audit lock box unit that stores unmodified valid coupons for eventual audit. The system further includes a rejected coupon lock box unit for temporarily storing selected coupons that were rejected by the coupon scanner but which were still redeemed by store personnel. The stored rejected coupons are later analyzed by a third party service provider to determine if they were validly redeemed by the store.