PROBLEM TO BE SOLVED : To enable precise and efficient real estate security management for a real estate spanning a plurality of copies and a plurality of mortgages. ?SOLUTION : This system comprises a copy classification processing means 12 for comparing a predetermined comparative processing order with a setting order of mortgage in registration, determining a non-mixing group when the comparative processing order is matched to the setting order, determining the other company mixing group when the comparative processing order and the setting order are differed in the other company mortgage, and determining an own company mixing group when the comparative processing order and the setting order are differed in own company mortgage, and dividend processing means 13, 14 and 15 each performing the dividend calculation of the non-mixing group, the other company mixing group, and the own company mixing group for every group, updating the amount of dividend based on the dividend calculation result, and performing the dividend calculation of the next group based on the updated amount of dividend. ?COPYRIGHT : (C)2005, JPO&NCIPI ?