The judgment below

The part against the Defendant is reversed, and that part of the case is remanded to the Seoul High Court.

Plaintiffs.

The grounds of appeal are examined (to the extent of supplement in case of supplemental appellate briefs not timely filed).

1. Where a business entity individually determines the sale price of a resettled housing site by applying a gap within the scope of discretion with respect to the grounds of appeal by the remaining plaintiffs except Plaintiffs AV, BF, BG, BG, BL, BU, and CG among the plaintiffs, the development cost of the entire resettled housing site may be deemed to have been differentiatedly allocated in accordance with the site location conditions for the individual resettled housing site. Thus, when calculating the development cost of the individual resettled housing site and the cost of installing basic living facilities and the reasonable sale price accordingly, the relevant gap shall be calculated by reflecting the relevant difference

(See Supreme Court Decision 2014Da11406 Decided August 20, 2014; Supreme Court Decision 2014Da6572 Decided August 20, 2014; Supreme Court Decision 2016Da231556 Decided August 30, 2018; etc.). Examining the relevant legal principles and records, the calculation of the difference applied by the Defendant at the time of calculating the amount of unjust enrichment is justifiable, and there was no error of misapprehending the legal principles on the application of the gap rate.

2. As to the Defendant’s ground of appeal

A. The part of the special supply contract that included the basic cost of living facilities in the sale price is in violation of Article 78(4) of the former Act on Acquisition of and Compensation for Land, etc. for Public Works Projects (amended by Act No. 8665 of Oct. 17, 2007; hereinafter “former Public Works Act”) if the person subject to relocation measures was to pay the project operator the cost of the basic cost of living facilities by including the cost of the basic cost of living facilities in the sale price.