1. The appeal by the independent party intervenor and the claims added by this court are all dismissed;

2. Appeal;

1. The first instance court rejected the Plaintiff’s primary principal suit against the Defendant, dismissed the Intervenor’s conjunctive principal suit against the Intervenor, and rejected the Intervenor’s claim against the Plaintiff, but rejected the Defendant’s claim against the Plaintiff.

Since only the intervenor appeals against the part of the judgment of the court of first instance against this part of the judgment of the court of first instance, the subject of the judgment of the court of first instance is limited to the intervenor's claim against the defendant.

In addition, since the intervenor added a claim for damages due to illegal acts to the defendant in the trial court, this part is also subject to the trial of the party.

2. The reasoning of the judgment of the court of first instance, which cited the judgment of the court of first instance, is the same as the ground of the judgment of the court of first instance, except for adding the judgment under paragraph (3) below.

3. Judgment added by this Court

A. 1) On the starting point of the statute of limitations for the right to claim restitution of unjust enrichment in this case, the intervenor did not know the fact of unjust enrichment itself in relation to the establishment of the right to claim restitution of unjust enrichment in this case. It is too harsh that the defendant could exercise his right on December 15, 2008 with respect to the intervenor who was confiscated by the invalid public sale procedure of this case from the point of time when the security deposit was distributed to him, which is the time when the defendant received the security deposit was distributed, and the legal reasoning of the Supreme Court Decision 2000Da31168 Decided April 27, 2001 is cited in this case, arguing that the ground for the claim for the return of unjust enrichment against the defendant in this case is invalid in the public sale procedure of this case, and such right to claim restitution of unjust enrichment has already been established at the time of payment without legal cause.