1. The plaintiff's claim is dismissed.

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

The Plaintiff supplied ready-mixed to C Co., Ltd. on December 1, 2008 (hereinafter “principal debtor”) and the Defendants jointly and severally guaranteed the obligation to pay ready-mixed prices to the Plaintiff of the principal debtor, and the fact that the unpaid ready-mixed price was 64,676,580, does not conflict between the parties.

The defendants also set up a defense that the guaranteed obligation was extinguished because the principal obligation became extinct by prescription.

The Plaintiff’s claim for ready-mixed against the principal obligor is subject to three years of extinctive prescription in return for the goods sold by the merchant (Article 163 subparag. 6 of the Civil Act). The Plaintiff did not assert or prove particular grounds for interrupting prescription against the principal obligor. The principal obligation of this case was extinguished by extinctive prescription on May 30, 2012, as claimed by the Defendant.

Therefore, since the guaranteed obligation of the Defendants was extinguished in accordance with the subsidiary nature of the guaranteed obligation, the Defendants’ defenses by the Defendants are reasonable, and the Plaintiff’s claim of this case is without merit.