1. Each of the plaintiffs' claims is dismissed.

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

1. Facts of recognition;

A. On May 26, 2015, the Defendant was awarded a contract for the rearrangement project in Yongcheon-si (hereinafter “instant rearrangement project”) with the price of KRW 1,596,977,00 (including value-added tax) and the period from June 2, 2015 to February 26, 2016.

B. 1) The Defendant is Nonparty L Co., Ltd. (hereinafter “L”) around June 25, 2015.

B) On July 2, 2015, the Defendant entered into a subcontract with L to 705,142,000 (including value-added tax) and the construction period from July 2, 2015 to February 20, 2016 with respect to the instant reinforced concrete construction among the instant rearrangement projects (hereinafter “instant reinforced concrete construction”).

In addition, on September 23, 2015, the Defendant entered into a subcontract with M Co., Ltd. (hereinafter “M”) with the content that the construction cost for the instant improvement project shall be KRW 210,336,00 (including value-added tax) and the construction period shall be from October 1, 2015 to February 20, 2016.

In addition, among the instant rearrangement projects, L actually implemented L, excluding the above reinforced concrete construction and its coverting construction (i.e., 175,422,00 won (i.e., 090,900,000 won-705, 142,000 won-210, 336,000 won) and the remainder of the construction works (i.e., the construction cost) excluding the above reinforced concrete construction and its covering construction). However, in the form of form,

3) L is a N Co., Ltd. (hereinafter “N”) at the time of entering into a subcontract for the said reinforced concrete construction project.

(2) On May 20, 2016, L was issued with a performance guarantee insurance policy and delivered to the Defendant. L was delivered to L around May 26, 2016 with an insurance coverage amounting to KRW 88 million with respect to the instant reinforced concrete construction (a pre-paid guarantee bond was issued and delivered to the Defendant; the Defendant issued an advance payment to L around May 26, 2016.