1. The plaintiff's appeal is dismissed.

2. The costs of appeal shall be borne by the Plaintiff.

Purport of claim and appeal

1...

According to Article 70(1) of the Civil Procedure Act and Articles 67(1) and (2) and 70(2) of the same Act, the scope of the judgment of this court is to be applied mutatis mutandis pursuant to Article 70(1) of the same Act and Articles 70(1) and (2) of the same Act, all of the co-litigants shall be judged in the case of preliminary co-litigation, and all of the co-litigants shall be effective only for the benefit of all the co-litigants. The litigation of one of the co-litigants against one of the co-litigants shall be effective for all the co-litigants. Thus, if an appeal is filed against either the main co-litigants or the conjunctive co-litigants, the part of the claim against the other co-litigants shall also be transferred to the appellate court, and shall be subject to the judgment of the appellate court (see Supreme Court Decision 2006Du17765, Mar. 27, 2008). In this case, the plaintiff filed a claim for the return of unjust enrichment against the defendant at the first preliminary claim

The first instance court dismissed both the primary claim and the first preliminary claim, and accepted the second preliminary claim against the defendant B, and the plaintiff appealed only to the part against the defendant A.

Each of the above claims is aimed at compensating for losses suffered by the Plaintiff in purchasing Defendant A’s shares, and all of them cannot be accepted, or where it is deemed necessary to make a joint conclusion among all the parties because the judgment process on each claim is inevitably mutually combined because the grounds for judgment on one claim affected by the other claim.

Therefore, even if the plaintiff appealed only against the defendant A because the defendant A and the defendant B constitute preliminary or selective co-litigants, the part of the claim against the defendant B is transferred to this court.