1. All appeals filed by the plaintiffs are dismissed.

2. The costs of appeal are assessed against the Plaintiffs.

The purport of the claim and appeal is the purport of the appeal.

1. Basic facts

A. On September 29, 2008, the land in each of the instant case was owned by the network A (hereinafter “the network”). On September 29, 2008, the maximum debt amount of KRW 2.1 billion, the debtor, the deceased, and the Defendant’s registration of the establishment of a neighboring mortgage (hereinafter “registration of establishment of each of the instant lands”) was completed, including the land of KRW 1,607 square meters, KRW 972 square meters prior to H, KRW 370 square meters prior to J, KRW 16,00 square meters prior to K, KRW 160 square meters prior to K, and KRW 14,922 square meters prior to L.

B. At the request of the inter-dong Agricultural Cooperative, a first-class mortgagee, the Gancheon District Court N, the voluntary auction procedure for each of the instant lands was conducted (hereinafter “instant auction procedure”). At the instant auction procedure, the Defendant received dividends of KRW 925,22,695 based on each of the instant collective security rights, and the Deceased received KRW 10,290,358 as the debtor and owner.

C. On March 28, 2014, the Deceased died during the instant lawsuit, and the Plaintiffs (the deceased’s grandchildren) jointly inherited the Deceased.

[Ground of recognition] Facts without dispute, Gap evidence Nos. 1, 2, and 8 (including branch numbers; hereinafter the same shall apply), the purport of the whole pleadings

2. Determination

A. The registration of the establishment of each of the instant neighboring areas by the Plaintiffs (A) is null and void as the cause was completed by means of the documents forged by M and the deceased’s name. The registration of the establishment of each of the instant neighboring areas by the Defendant’s establishment of a mortgage cannot be deemed as a legal cause.

B) Therefore, the Defendant is obligated to return unjust enrichment to the Plaintiffs, who are the inheritor of the Deceased, to pay each of the KRW 462,611,340 and the delay damages, depending on their inheritance shares. (2) The Defendant entrusted M with the seal impression and identification card of the Deceased, and comprehensively delegated all of the affairs concerning the sale of real estate owned by the Deceased or lending.

The registration of the establishment of each of the instant establishments was made with the Defendant.