The appeal is dismissed.

The costs of appeal are assessed against the defendant.

The grounds of appeal are examined.

1. Regarding ground of appeal No. 1

A. A joint venture in the method of joint performance has the nature of a partnership under the Civil Act. An obligation of a partnership is a member’s obligation, and barring any special circumstance, a creditor of the partnership may exercise his/her right in proportion to the share of each member or equally. However, if the obligation of the partnership was to be borne by an act which is a commercial activity for all members, it is reasonable to authorize the joint and several liability of members by applying Article 57(1) of the Commercial Act (see, e.g., Supreme Court Decision 92Da30405, Nov. 27, 1992). If a member of a joint and several venture is a merchant of a joint and several venture, a member of the joint and several venture is jointly and severally liable to perform a defect repair

(See Supreme Court Decision 2012Da57590 Decided May 23, 2013, etc.). Meanwhile, the term “guarantee insurance” means a non-life insurance that takes over by an insurer the compensation of the damage to be borne by an insured (beneficiary under a main contract) due to a policyholder’s nonperformance of obligation under a certain legal relationship with the insured. In order to claim insurance under a guarantee insurance contract, two requirements are necessary that the occurrence of an insured event under a policyholder’s main contract and the occurrence of an insured’s property loss based on such occurrence (see Supreme Court Decision 99Da3693, Jun. 22, 1999). In the event a joint venture member concluded a warranty insurance contract based on the investment ratio individually, if an insured subcontractor fails to perform his/her obligation within the performance period, the insurer is the insured contractor due to the occurrence of an insured incident and property loss.