To automatically set an affiliate only by recommending a commodity in response to a commodity search request without performing a troublesome operation.

This commodity search bulletin board device includes: a request contribution receiving means for receiving a request contribution to commodity search from a user's terminal; a recommendation contribution receiving means for receiving a recommendation contribution to the request contribution from another user's terminal and embedding tracking information including the identifier of a user who has performed the recommendation contribution in a commodity page address included in the recommendation contribution; and an affiliate managing means for identifying purchase results through a commodity page shown by a commodity page address included in the recommendation contribution with the tracking information, and giving a reward to the user who has performed the recommendation contribution.