Patent ID: 7542927

Claim:
A product purchase method using a computer network comprising the steps of: updating, via said computer network, order sheet data stored in a database included in a server, wherein said order sheet data is order sheet data for each buyer; inhibiting the updating of said order sheet data after a predetermined date, wherein, until said predetermined date is reached, said order sheet data for each buyer can be corrected by respective buyers at any time via said computer network; aggregating said order sheet data of each buyer by summing up quantities of ordered products for each type of the ordered products to obtain aggregated data after said predetermined date; fixing, as order data, said order sheet data for each buyer and said aggregated data after said predetermined date; delivering said ordered products to the respective buyers based on said order sheet data; and storing delivery confirmation as information corresponding to said order sheet data for each buyer in said server when buyers confirm delivery of said ordered products, whereby said buyers can refer to a status of said delivery at any time via said computer network.