1. All of the plaintiffs' claims are dismissed.

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

1. Basic facts

A. The deceased E (hereinafter “the deceased”) married with F, and had the Plaintiffs, Defendant G, and H between them, and died on October 12, 2015.

B. The Deceased owned each of the real estate indicated in the separate sheet (hereinafter “instant real estate”) but changed the said maximum debt amount to KRW 63 million on November 15, 2001, regarding the instant two real estate to the International Cooperatives, the amount of the maximum debt amount to KRW 39 million on August 1, 201, and the maximum debt amount to KRW 26 million on January 21, 2015, with KRW 169 million on January 5, 2015.

On May 12, 2015, each of the instant real estates was set up as a joint collateral, and was added to each of the instant real estates on May 12, 2015, and on the same day, each of the instant real estates was set up with a maximum debt amount of KRW 650 million.

(hereinafter “each of the instant mortgages”) C.

on April 29, 2015, F entered into a sales contract for K of the Seoul Central Building in Jung-gu, Seoul, and completed the registration of ownership transfer on May 28, 2015, and the entire registration certificate is written with the transaction value of KRW 369 million.

From April 29, 2015 to May 28, 2015, the above purchase price was released from the deceased’s account.

On August 25, 2015, the Deceased entered into a sales contract with the Defendant to acquire the purchase price of each of the instant real estate, each of the instant collateral obligations was completed on August 26, 2015, and on August 26, 2015, the Defendant completed the registration of transfer of ownership on the instant real estate (hereinafter “instant sales contract”); and on September 8, 2015, the Defendant changed the debtor to the debtor on the ground of contract acceptance (the secured debt of each of the instant collateral was KRW 780 million at the time), and completed the registration of change of each of the instant collateral security rights to the Deceased on August 24, 2015 (the secured debt of each of the instant collective security rights was KRW 70 million at the time, KRW 70 million on August 24, 2015, KRW 985 million on August 25, 2015, = 850 million on August 8, 2015, respectively.