2. The plaintiff's claim is dismissed.

3. All costs of the lawsuit shall be borne by the Plaintiff.

A. The Plaintiff is a construction company with the main purpose of indoor building business, and the Defendant is a construction company with the main purpose of building business, which has completed registration in accordance with each Framework Act on the Construction Industry.

B. On December 9, 2016, the Defendant entered into a construction contract with C Co., Ltd. (hereinafter “C”) with the content that the Defendant would receive KRW 3,03,800,000 (including value-added tax; hereinafter the same shall apply) as the construction cost from C and that the Defendant would newly construct the main complex building on D and E’s ground (hereinafter “instant prime contract”) by October 31, 2017.

Around October 25, 2017, the Defendant and C agreed to increase the construction cost in KRW 3,575,000,000 and to extend the construction period until December 31, 2017 to change the contents of the instant original contract.

C. On January 11, 2017, the Plaintiff and the Defendant concluded a subcontract for construction works with the purport that the Plaintiff shall complete the interior and the part of the main complex construction works (hereinafter “instant subcontracted construction”) among the construction works for the construction of a main complex building (hereinafter “the instant main construction works”) under the instant prime contract, upon receiving KRW 121,00,000,00 as subcontract consideration from the Defendant, by July 15, 2017 (hereinafter “instant subcontract”), and entered into a contract with the following special terms and conditions therein:

On March 31, 2017, the Plaintiff and the Defendant agreed to increase the subcontract price in KRW 220,000,000, and to revise the contents of the instant subcontract by extending the construction period until September 30, 2017. The Plaintiff and the Defendant agreed to change the contents of the instant subcontract by reducing the subcontract price in KRW 193,00,000 for the fixed and irregular subcontract price at KRW 193,00.

Terms and Conditions of Contracts

1. The contract price shall not be changed unless the subcontractor changes the amount calculated and prepared by the subcontractor on the basis of the drawings provided;

2. To submit a performance guarantee immediately after the preparation of this contract and to complete the work;