2. The costs of lawsuit shall be borne by the Plaintiff.

A. On September 27, 2016, the Defendant concluded each contract for construction with C Co., Ltd. (hereinafter “C”) and each contract for construction, which was contracted for the installation and dismantling of a non-system in the year between 2016 and 17, and June 2, 2017 to 2017.

(hereinafter the above construction works are referred to as the "instant construction works", and each of the above construction contracts is referred to as the "instant construction contract."

On June 14, 2017, the Defendant entered into a contract with the Plaintiff for the construction period of “D 7L 57 K-related non-contract” from June 14, 2017 to August 31, 2017 with the contract amount of KRW 90,459,50 (including value-added tax; hereinafter the same shall apply). On June 26, 2017, the Defendant increased the construction amount on June 26, 2017, and entered into a subcontract with the Plaintiff for the construction period of KRW D 50,500,000 during the construction period (hereinafter the “subcontract”).

Article 15(1) of the “Construction Contract” attached to the instant subcontract agreement provides, “If the prime contractor has received an adjustment of the contract amount from the ordering person for the reasons of the price or fluctuation of charges for items after the conclusion of the contract, etc., if additional expenses are to be incurred in the completion of the object for the same reason, the subcontractor shall be paid after adjusting the contract amount according to its content and proportion. In such cases, the prime contractor shall make an adjustment of the subcontract amount within 30 days from the date of receiving such adjustment from the ordering person.

C. The Plaintiff continued the instant subcontract construction in accordance with the instant subcontract agreement and completed the construction work around August 2018.

The provisions of the Fair Transactions in Subcontracting Act (hereinafter “subcontract”) related to the instant case are as follows.

Article 16 (Adjustment of Subcontract Prices Following Change of Design, etc.) (1) The principal contractor shall entrust the manufacture, etc.