1. Revocation of the judgment of the first instance, and the plaintiff's primary claim is dismissed.

2.The preliminary claims added at the trial.

1. Facts of recognition;

A. On December 29, 2016, the Plaintiff entered into a sales contract with the Defendant to purchase KRW 13 million (hereinafter “instant sales contract”). On the same day, the Plaintiff paid KRW 13 million to the Defendant the purchase price.

B. On July 12, 2017, the Korea Land and Housing Corporation publicly announced that the change of purchaser's name can be made after the first buyer entered into a sales contract, and that the regulations under relevant laws, such as Article 19-2 of the Housing Site Development Promotion Act and Article 13-3 of the Enforcement Decree of the same Act should be complied with.

C. On July 14, 2017, the Defendant acquired the instant sales right by means of a lottery held by the Korea Land and Housing Corporation.

On July 17, 2017, the Plaintiff paid KRW 20 million to the Defendant under the name of the sales contract to be paid by the Defendant to the Korea Land and Housing Corporation according to the instant sales contract, and the Defendant entered into a housing site supply contract with the Korea Land and Housing Corporation on July 19, 2017.

[Ground of recognition] Facts without dispute, entry of Gap 1 through 7, 9 evidence, purport of the whole pleadings

2. Determination

A. According to the above facts as to the main claim, the defendant is obligated to implement the procedure for change of the name of the sale right of this case to the plaintiff according to the sales contract of this case, barring any special circumstances, and the defendant argues that the sales contract of this case is null and void because it violates the related Acts and subordinate statutes, such as the Housing Site Development Promotion Act, etc

Article 19-2 of the Housing Site Development Promotion Act and Article 13-3 subparagraph 1 of Enforcement Decree of the same Act prohibit, in principle, a person who has been supplied with a housing site created under the Housing Site Development Promotion Act from reselling the housing site as it is without using the housing site for the purpose of being supplied with the housing site until the registration of ownership transfer.