1. All of the plaintiffs' claims are dismissed.

2. The costs of lawsuit are assessed against the plaintiffs.

1. Basic facts

A. A. The name of the Plaintiff Co., Ltd. (hereinafter “Plaintiff’s name”) is a company that newly constructs apartment and ancillary and welfare facilities with 207 households in Ulsan-gu, Ulsan-do (hereinafter “1 apartment complex”), and the Plaintiff Co., Ltd. (hereinafter “Plaintiff’s name construction”) is a company that newly constructs apartment and ancillary and welfare facilities with 205 households in the number of 56 days in Ulsan-gu, Ulsan-gu (hereinafter “2 apartment complex”) and the Defendant is a company that constructs apartment and ancillary and welfare facilities with 205 households in the number of 56 days in the number of Ulsan-gu, Ulsan-gu.

B. On March 2013, the contract was concluded between the Plaintiff and the Plaintiff regarding the new construction of apartment complex, the Defendant entered into a contract with the Plaintiff for the construction cost of KRW 32,568,60,000 for the new construction of apartment complex; the construction cost of KRW 27,49,273,00 for the new construction of apartment complex (hereinafter collectively referred to as the “each of the instant new construction works”); and the construction cost of KRW 27,49,273,00 for the new construction of apartment complex; and the contract for the construction of the construction period of KRW 24 months from the commencement date of the construction period (hereinafter referred to as the “each of the instant contracts”).

The main contents of each of the terms and conditions of the instant contract (hereinafter “instant general terms”) and the special terms and conditions (hereinafter “instant special terms and conditions”) are as follows.

Article 15 [Adjustment of Contract Amount due to Modification of Design] (1) When the contents of a design do not coincide with the condition of the construction site, is unclear, omitted or erroneous, or unexpected circumstances arise in relation to construction, or when the installation of additional facilities is required due to the modification of a project plan, etc., a contractor shall modify the design.

(2) Where the volume of construction works increases or decreases due to the modification of a design under paragraph (1), the contract amount shall be adjusted according to the following standards, and if necessary, the construction period shall be extended or shortened

Article 16. Other.