1. All of the plaintiffs' claims are dismissed.

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

In Seoul Central District Court Decision 2016Gahap3848, the court held that the Plaintiff Company A borrowed KRW 2.3 billion from the Daechi Mutual Savings and Finance Company, and the Defendant jointly guaranteed the above loan and joint and several surety obligation, and that the Defendant acquired the above loan and joint and several surety obligation, and that the Defendant would pay the Defendant the amount of KRW 2.3 billion to the Defendant, but the Plaintiffs otherwise asserted that there was no loan from Daechi Mutual Savings and Finance Company 2016Gahap3848, and that there was no joint and several obligation based on the final judgment in the above Seoul Central District Court Decision 2016Gahap3848.

However, since the assertion or defense arising from the grounds that could have occurred and submitted before the closing of argument in the final and conclusive judgment is interrupted by res judicata of the final and conclusive judgment, it is not allowed for the parties to make a new assertion contrary to the contents of the final and conclusive judgment on such grounds (see Supreme Court Decision 2015Du44288, Oct. 29, 2015). The above Seoul Central District Court Decision 2016Da3848, Oct. 11, 2016, which became final and conclusive on Oct. 11, 2016, is significant in this court. Since the above plaintiffs' assertion is based on the grounds that the above plaintiffs could have occurred and submitted before the closing of argument in the final and conclusive judgment, it is not acceptable as it conflicts with the res judicata effect of the final and conclusive judgment.

Therefore, each of the claims by the plaintiffs in this case is dismissed as it is without merit.