A coupon clearinghouse server receives a request for a coupon offer from a client device. The server transmits only a first subset of coupon offer data for the coupon offer to the client device, and stores, in memory, a first code for a first merchant at which the coupon offer is redeemable. The code is not revealed to the client device. Subsequently, the server receives, from the client device, a second code that the client device has obtained at a point of sale system. The server determines if there is a match between the first code and the second code, and if so, transmits the second subset of coupon offer data including coupon offer redemption instructions to the client device. The client device presents the now complete coupon offer to the point of sale system to redeem the coupon offer.