1. The plaintiff's claim is dismissed.

2. The costs of the lawsuit, including costs incurred by participation, are all assessed against the Plaintiff.

1. Basic facts

A. The Plaintiff is a company established for the purpose of manufacturing and selling valves, etc., and the Defendant is a company established for the purpose of manufacturing, selling, importing, and exporting and importing measuring control equipment, pipes materials, valves, etc.

B. 1) Co., Ltd. E (hereinafter “E”) between the parties

(A) On July 4, 2014, the Intervenor joining the Defendant (hereinafter referred to as the “Supplementary Intervenor”)

with respect to the F Project, the gas measurement system (hereinafter referred to as the “instant system”) shall be

(2) On December 10, 2014, the Defendant ordered two MOV Ball Valves to be used in the instant system to the Plaintiff, the supply price of 434,387,000 won and the payment period of 10 May 10, 2015.

(3) On December 19, 2014, the auxiliary intervenor entered into a contract with the Defendant for the purchase of KRW 578,000 (excluding value-added tax) to be used for the instant system from the Defendant. On June 24, 2015, the supplementary intervenor entered into a contract for the purchase of KRW 578,000 (excluding value-added tax) with the Defendant. On June 16, 2015, the supplementary intervenor entered into an order with the Defendant for the purchase of KRW 578,00,00 (excluding value-added tax) (excluding the payment period under the written order).

(4) On June 23, 2015, the Plaintiff entered into a guarantee insurance contract with G Co., Ltd. (hereinafter “instant guarantee insurance contract”) with the effect that, in the event of a defect in the performance of the instant contract, a maximum of KRW 43,438,700 shall be paid to G Co., Ltd. to the Defendant as damages for defect repair.

5) The Defendant shall make the valves listed in the separate sheet from the Plaintiff (hereinafter referred to as the “instant valves”).

(C) The Plaintiff, an employee of the Plaintiff, forged a design-level test conformity certificate and an official seal of the Korea Gas Safety Corporation with respect to the valves to be supplied to the Defendant, and the Defendant.