Order processing device, issuer device, and system

An order processing device connected via a network to a plurality of user devices respectively operated by a plurality of users and to an issuer device operated by an issuer of a financial instrument,

• the plurality of user devices transmitting, to the order processing device, one or more pieces of order information that designates a trading type indicating a “sell” or a “buy” of the financial instrument, a price of the financial instrument, and an amount of the financial instrument,
• the issuer device transmitting either collectively or one at a time, to the order processing device, two or more pieces of order information that designate a trading type indicating a “sell” of the financial instrument, a price of the financial instrument, and an amount of the financial instrument,
• the two or more pieces of order information, which designate a trading type indicating a “sell” and which are transmitted by the issuer device, including two or more pieces of order information which designate different prices,
• the order processing device:
• including an order information storage device and an execution information storage device;
• receiving order information respectively from the plurality of user devices and the issuer device and storing in the order information storage device the respective pieces of received order information;
• matching and executing order information of which trading type indicates a “sell” and order information of which trading type indicates a “buy” from among the pieces of order information stored in the order information storage device, and deleting the executed order information from the order information storage device, and storing execution information in the execution information storage device;
• and
• in a case where the issuer device transmits, one at a time, two or more pieces of order information that designate a trading type indicating a “sell” and where a total of two or more pieces of order information that designate a trading type indicating a “sell” is not received within a predetermined period from the issuer device, discarding or invalidating all of the pieces of order information which designate a trading type indicating a “sell” and which have been received from the issuer device.