2. As to the grounds of appeal on the conjunctive claim (to the extent of supplement in case of supplemental appellate briefs not timely filed)

A. In order for a payment in substitutes to take effect of the extinguishment of an obligation, other benefits provided by the obligor in lieu of the original performance must be realistic. In such a case, when other benefits are transferred to the ownership of real estate, it is not sufficient to deliver either the intention of the party concerned or the certificate of the personal seal impression, and the registration that takes effect of change in the real right to such real estate is completed (see, e.g., Supreme Court Decision 82Da1758, Jun.

Meanwhile, in a case where two or more persons agree to divide ownership among one building, the location and size of which are specified, and which are independent in structure and use, and the registration is made at the proportion corresponding to the size of each sectional ownership for convenience, mutual title trust relation between sectional owners or sectionally owned co-ownership relation to the building (see, e.g., Supreme Court Order 2000Ma2633, Jun. 15, 2001; Supreme Court Decision 2011Da42430, Feb. 27, 2014).

B. Review of the reasoning of the lower judgment and the record, including the duly admitted evidence, reveals the following facts.

(1) Around May 9, 2006, the Defendant entered into a contract for construction works with B, and Seo-gu, Daejeon-gu, for the construction work of which the construction cost is 6 billion won (including value-added tax) for the construction of the building on the first basement and the 6th floor above the ground (hereinafter referred to as the “instant building”) on the land of 3023.7 square meters (hereinafter referred to as the “instant land”). On August 1, 2008, the Defendant entered into an agreement on May 29, 2008 to increase the construction cost as 6.6 billion won (including value-added tax) and completed the instant building on August 1, 2008.

(2) Meanwhile, on March 31, 2008, B and C agreed to accord and sell the first floor of the instant building to the Defendant in lieu of paying the construction cost liability as to the instant building. Accordingly, around May 7, 2008, B, C and the Defendant changed the name of the owner of the instant building into the joint name of B, C and the Defendant three persons.

(3) On May 8, 2008, the Defendant entered into a lease agreement with G Agricultural Cooperatives (hereinafter referred to as “GFFF”) as to the first floor of the instant building and the corresponding land share amounting to KRW 3 billion, KRW 20 million monthly rent (excluding value-added tax), and the period from June 1, 2008 to May 31, 2018.

(4) On June 3, 2008, B and C prepared a letter of commitment to the settlement of accounts with the defendant on June 3, 2008 (Evidence No. 30-1, hereinafter referred to as the "certificate of this case"). With respect to the new construction of the building of this case, the defendant set the amount of the pre-execution on behalf of B and C and the amount to be subsequently executed (Article 1(1), hereinafter referred to as the "amount of substitute payment") and confirmed that the unpaid construction cost is KRW 3.672 million (Article 1(2), hereinafter referred to as the "construction cost of this case"). On the other hand, the first floor of the building of this case and the corresponding share of the land of this case are evaluated as KRW 8 billion (excluding value added tax), and agreed to appropriate the amount of substitute payment of this case and the share of this case to the construction cost of this case in succession after July 30, 2008 (Article 2).

(5) However, the Hyundai Pus Co., Ltd., which entered into a sales contract with the Defendant to purchase the instant building, filed an application for provisional injunction against the Defendant to dispose of the instant building with the Defendant, and the provisional injunction registration was completed on July 15, 2008 with respect to the instant building on the commission of the provisional injunction registration following the provisional injunction decision.

(6) On July 29, 2008, the Defendant completed the registration of the establishment of chonsegwon from June 1, 2008 to June 5, 2018 with respect to the first floor of the instant building on the ground of the contract made by the GF on May 8, 2008, and operated a store with the name of "JEart" from October 5, 2008 after receiving the first floor of the instant building from the Defendant on August 2008.

(7) On the other hand, around May 2006, B and C provided the instant land as collateral and extended the payment period. As to the instant building, on July 30, 2008, the registration of preservation of ownership was completed on the debtor as to B and C’s share among the instant building on July 30, 2008, and the Defendant completed the registration of creation of a mortgage over the third priority of maximum debt amount of KRW 3.9 billion with respect to his share of the instant building B and C as the debtor B and C. On the same day, the foreign exchange bank completed the registration of creation of a mortgage over the third priority of maximum debt amount of KRW 3.9 billion with respect to his share of the instant building to B and C.

(8) Meanwhile, although the instant building is a single building, the parts classified from the first floor to the 6th floor above the ground level could be independently used as an independent building. On July 28, 2008, the Defendant, B, and C submitted to the head of Seo-gu Daejeon Metropolitan City, Daejeon, an application for a change in the building management ledger stating that "the first floor owner, the second to the sixth floor owner, and the second to the third floor owner, after having agreed to own the instant building as a collective building B and C, shall be changed to the ownership of the instant general building as a collective building and obtain approval for use." Accordingly, an application for a change in the building management ledger stating that "the ownership of the instant general building on the land shall be changed to the ownership of the collective building as a collective building, and the collective building ledger on the instant building was newly created with the approval for use, and the parts of the first floor in the said collective building ledger were registered as well as subparagraphs 101 (hereinafter referred to as "Article 101") and 102, the remaining floors were owned by both subparagraphs 1 and 2, 301 and 401 (1).

(9) The subsequent decision to commence the sale of real estate was rendered on December 10, 2008 at the request of the foreign exchange bank, which is a mortgagee, with respect to the instant land and building. The Plaintiff purchased the instant land and building from the above auction procedure on March 18, 2010 and completed the registration of ownership transfer in its name on the same day.

(10) Meanwhile, on March 18, 2010, the instant building was amended as an aggregate building registration due to the error in application in accordance with the said aggregate building ledger, and the registration of the instant building was entered in the register of each partitioned building at that time. Examining the foregoing facts in light of the aforementioned legal principles, the following circumstances are revealed.

The instant building has independence in structure and use, which can be classified into floors, including part of the first floor (as separate registration No. 101 and No. 102), and has agreed to be owned by the Defendant as a payment in lieu of the obligation to pay the construction cost to the Defendant by the contractor B, C and the Defendant under the instant promise.

For this purpose, the name of building permit B, C, and the Defendant changed jointly. On July 15, 2008, the entrustment of the above provisional disposition registration completed the procedure of registration of ownership preservation on their co-ownership. However, even while maintaining the registration of ownership preservation being co-owned, subparagraphs 101 and 102 in the above aggregate building register were owned by the Defendant, as in the previous agreement, and the remaining parts were owned by B and C, the agreement was reached between B and C to establish the co-ownership relationship under the mutual title trust agreement with respect to the remaining parts of the building.

Therefore, the registration in the name of the Defendant, made with respect to the portion 1/3 of the instant building, was registered in accordance with the substantive relationship under the agreement on co-ownership of divided ownership and mutual title trust agreement. Accordingly, between B, C and the Defendant, the ownership under subparagraphs 101 and 102 was reverted to the Defendant by the said registration, thereby completing the performance of accord and satisfaction under the instant promise. Furthermore, it is reasonable to view that the value of the first floor of the instant building, the instant substitute payment, and the instant construction cost have been settled within the scope of the settlement, and the construction cost of the instant building is extinguished.

D. Nevertheless, the lower court determined otherwise, based on the erroneous determination that there was no evidence to acknowledge that the Defendant, in the process of acquiring the ownership of the portion of the first floor of the instant building by transfer, that is, in the process before and after the process of the registration procedure for initial ownership preservation, there was no evidence to acknowledge that the Defendant expressed the intent to complete the reservation in accordance with the above accord and satisfaction agreement or expressed the intent to accept the said share as a substitute benefit, and concluded that the obligation to pay the instant construction cost does not expire with respect to the said accord and satisfaction, and that the Defendant may exercise a lien on the second floor and the third floor of the instant building with the payment obligation as the secured claim.

Therefore, the court below erred by misapprehending the legal principles as to the validity of payment in kind and establishment of sectionally owned co-ownership relationship, thereby failing to exhaust all necessary deliberations. The ground of appeal assigning this error is with merit.

3. Conclusion

Therefore, without further proceeding to decide on the remaining grounds of appeal, the part concerning the conjunctive claim among the judgment below is reversed, and that part of the case is remanded to the court below for further proceedings consistent with this Opinion. The appeal on the plaintiff's primary claim is dismissed. It is so decided as per Disposition by the assent of all participating Justices on the bench

Note Justice Kim Gin-deok

Justices Kim Jae-han

Justices Lee Dong-won