Patent ID: 8612338

Claim:
A purchase information collecting method for collecting information on a purchaser of one or more commodities using a network with a server apparatus, the method comprising: executing using a processing device: receiving a first sales information, which identifies a deal of a first commodity, from a retail seller of the first commodity, wherein the first sales information is generated by the retail seller of the first commodity and identifies the retail seller of the first commodity and identifies a time and place at which the first commodity was sold by the retail seller of the first commodity; storing the received first sales information in a first storing part; receiving purchase information, which comprises personal information of a purchaser of a second commodity and a second sales information, from the purchaser of the second commodity, where the second sales information is generated by a retail seller of the second commodity when the second commodity is sold, and where the second sales information identifies the retail seller of the second commodity and identifies a time and place at which the second commodity was sold by the retail seller of the second commodity; based on the retail sellers, times and places identified by the first sales information and the second sales information, determining whether the second sales information included in the received purchase information is stored in said first storing part; storing the received purchase information as valid purchase information in a second storing part upon the second sales information being stored in the first storing part; extracting sales information containing a first information of the purchase information from said first storing part upon the second sales information included in the received purchase information not being stored in the first storing part, including a range of deal numbers of a second information between a minimum deal number of the second information to a maximum deal number of the second information; storing the purchase information as invalid purchase information in the second storing part upon the second information of the purchase information having a deal number that is within the a range of deal numbers of a second information between a minimum deal number of the second information to a maximum deal number of the second information; and storing the purchase information as unidentified validity purchase information in the second storing part upon the second information of the purchase information not having a deal number within the range of deal numbers.