The defendant shall pay to the plaintiff 27,175,753 won with 5% interest per annum from March 2, 2013 to December 19, 2013, and 20% interest per annum from the next day to the day of full payment.

2. The plaintiff's remaining appeal and the claim extended in the trial and the defendant's incidental appeal are all dismissed.

3. 10% of the total litigation costs shall be borne by the Plaintiff, and the remainder by the Defendant, respectively.

4. The portion of payment of the amount under paragraph (1) may be provisionally executed.

2. Purport of appeal: The judgment of the first instance court is modified as follows. It is so decided as to the purport of appeal.

3. Purport of incidental appeal: The part against the defendant among the judgment of the court of first instance against is revoked, and the plaintiff's claim corresponding to the revocation is dismissed.

The court's explanation on this part is consistent with the reasoning of the judgment of the court of first instance, and this part is cited in accordance with the main sentence of Article 420 of the Civil Procedure Act.

2. Determination on the defense prior to the merits

The defendant asserts that the lawsuit of this case seeking the return of overdue interest, in which the plaintiff's obligation to pay overdue interest was delayed and the defendant would return it to the plaintiff, the defendant would impose the charges added to a new liquidation cost on the members of the defendant's association, thereby accompanying the sacrifice of the defendant's members. Thus, the defendant asserts that there is no benefit in the protection of rights. However, it is insufficient to recognize the circumstance that the evidence submitted by the defendant alone brought the lawsuit of this case for the purpose of causing pain to the defendant, or that there was no benefit in the protection of rights, even though the plaintiff did not have any benefit. The ground alleged by the defendant alone is contrary to the principle of good faith or it is difficult

3. Judgment on the grounds of claim

A. The parties' assertion

The plaintiff asserts to the effect that, although the overdue interest on the shares of the union members was paid to the defendant, since the shares of the union members to be borne by the plaintiff was reduced due to the change of the management and disposal plan, 36,284,950 won, which is the difference between the overdue interest calculated according to the changed shares among the overdue interests on the original shares, is invalidated and that the defendant is obligated to return the shares to the plaintiff in unjust enrichment. Accordingly, the defendant asserts to the purport that the above change of the management and disposal plan was made after the new disposition to distribute the surplus to the union members according to the change of the ex post facto change of the management and disposal plan,

B. Determination

Unlike the case of modifying minor matters of a management and disposition plan, where a housing reconstruction and improvement project association formulates a new management and disposition plan to substantially alter the main parts of the original management and disposition plan and obtains authorization from the head of the Si/Gun, the original management and disposition plan shall lose its effect (Supreme Court Decision 2010Du19799 Decided February 10, 201, etc.).

According to the purport of subparagraph 3-1, 2, and 3 of the evidence No. 3-2, each of the following items and arguments, the management and disposal plan was made after the lapse of three years from the time of the previous management and disposal plan. The amendment of the relevant Act and subordinate statutes applies the estimated cost rate reflecting the changes in the sales revenue, expenses, etc. due to the conversion of the rental house into the general unit sale (Article 7(1)) into the unit sale (Article 7(1). It was made to finally determine the members’ contributions after the completion of the instant apartment (Article 9, 201). The management and disposal plan of December 29, 2012 explicitly stated “it is difficult to recognize the facts made for the alteration of the management and disposal plan to change the contributions to the members’ contributions imposed or refunded to the members. Moreover, it is difficult to view the contributions of the members’ contributions to be calculated based on the estimated cost ratio, and the estimated cost ratio is calculated based on the changes in the previous management and disposal plan as the main purpose of the members’ contributions to be altered.

Therefore, the defendant's overdue interest on the original contribution was based on the previous management and disposition plan that lost its validity, and thus, the defendant is obligated to return it to the plaintiff as unjust enrichment, since it is based on the previous management and disposition plan that has lost its validity as the revised contribution amount of KRW 331,826,822, not the overdue interest on KRW 33,829,00 [The overdue interest payment amount of KRW 115,610,920 x KRW 115,616,920 x KRW 116,000 x KRW 29.2616 (hereinafter omitted].

4. Judgment on the defendant's defense of offsetting

(a) Set-off against the claim for reimbursement of litigation costs;

According to the facts established in this court, Eul evidence 10 and the purport of the entire pleadings, the Seoul Central District Court Order 2012Kao-5569 dated January 22, 2013 determined the amount of litigation expenses that the plaintiff shall reimburse to the defendant with respect to the case, such as the Seoul Central District Court Order 2012Kadan89366, as KRW 1,507,746. The above decision becomes final and conclusive on March 1, 2013, and the legal brief dated June 24, 2013, stating the defendant's declaration of offset, was delivered to the plaintiff around that time. According to the above facts established above, the "when the period during which both parties' obligations have come due," which may be offset pursuant to Article 492 of the Civil Act, is the period during which the plaintiff's obligation to reimburse the litigation expenses against the defendant, and the plaintiff's claim for return of unjust enrichment of KRW 497Da397198, March 1, 2013

Therefore, the defendant's argument of set-off is justified.

(b) Set-off against the claim for refund of deposit;

The Defendant asserts to the effect that on December 10, 2012, the Plaintiff deposited KRW 5,094,411 as the principal deposit, and the Plaintiff paid it to the effect that it should be offset or deducted.

According to the evidence evidence No. 11, as of December 10, 2012, the defendant deposited KRW 5,094,411, which is the amount under the judgment of the court of first instance after deducting KRW 1,510,936 from the amount under the judgment of the court of first instance, by making the deposited person as the plaintiff as the plaintiff on the gold No. 24484 (the entry is not clear) of Seoul Central District Court in 2012. However, there is no evidence to acknowledge the fact that the plaintiff received the deposited amount without reservation, and the deposit of part other than the total amount of the debt does not take effect even with respect to that part (see Supreme Court Decision 2011Da83776, Mar. 15, 2012). Therefore, it is difficult to accept the defendant's allegation of set-off or deduction.

5. Conclusion

Therefore, the Defendant, as unjust enrichment, 33,781,100 won (i.e., KRW 33,829,09 - KRW 47,998 which has been extinguished by a set-off) and 6,605,347 won, which is the part cited by the judgment of the court of first instance, shall be set off against the Plaintiff, and 5% per annum prescribed by the Civil Act from March 2, 2013 to October 18, 2012, which is the date when the judgment of first instance, is rendered, and 20% per annum prescribed by the Act on Special Cases Concerning the Promotion, etc. of Legal Proceedings from the following day to the date when the payment is fully made; 27,175,753 won, which is the part to be ordered to be paid additionally at the remaining court of first instance, from March 2, 2013 to the date when the Defendant becomes liable to pay the amount of the obligation by set-off to the extent of the obligation.

Therefore, the plaintiff's claim shall be accepted within the scope of the above recognition, and the remaining claims shall be dismissed as it is without merit. Since part of the part against the plaintiff in the judgment of the court of first instance differs from this conclusion, it is unfair to accept part of the plaintiff's appeal and revoke it, and order the defendant to pay the above amount additionally recognized in the court of first instance. Since the remaining part of the judgment of the court of first instance is legitimate, the remaining part of the judgment of the court of first instance is legitimate, and the plaintiff's remaining appeal and the defendant's incidental appeal are dismissed as they are all

Judges Lee Jae-mo (Presiding Judge)

1) The difference between the modified contribution and the initial contribution 137,260,358 ± the original contribution 469,087,180 won