Patent ID: 7926713

Claim:
A settlement server configured to subtract a monetary value equivalent to a settlement amount demanded by a first settlement request server from a settlement execution terminal having stored a monetary value as electronic information, the settlement execution terminal configured to increase/decrease the monetary value based on amount update information, the settlement server comprising: a processor; and a memory device storing instructions which when executed by the processor, cause the processor to: (a) transmit: (i) a first seed to the first settlement request server; and (ii) a second, different seed to a second settlement request server; (b) receive, from the settlement execution terminal: (i) transaction identification information for identifying a transaction with the first settlement request server; (ii) the settlement amount; and (iii) a first calculation result for a predetermined calculation performed on the settlement amount, the first calculation result being determined by the first settlement request server, the first settlement request server using the first seed to determine the first calculation result; (c) determine a second calculation result by performing the predetermined calculation on at least the received amount and the first seed; (d) determine whether the second calculation result is equal to the received first calculation result; (e) determine whether the received amount is equal to the settlement amount; and (f) in response to the received amount and the settlement amount being equal, transmit, to the settlement execution terminal, amount update information for subtracting a monetary value equivalent to the received amount.