1. The former Act on Special Cases concerning the Partition of Co-Owned Land (amended by Act No. 4875 of Jan. 5, 1995 and effective March 31, 200; hereinafter “Special Act”) provides that no application for subdivision may be withdrawn after a decision to commence subdivision is made (the main text of Article 14(3)). Except in cases where there is no objection within the statutory period after a decision to commence subdivision is made or an objection is not accepted after a decision to commence subdivision is made, or where a decision to commence subdivision becomes final and conclusive, a decision to commence subdivision becomes final and conclusive (Article 21(2)), the application can only be made under the aforesaid Special Act (Article 21(2)). In addition, in light of the provisions of Article 32 of the Special Act on Special Cases concerning the Partition of Co-owned Land and Article 34 of the same Act, if there is no objection against the written protocol within the statutory period, or if a final and conclusive decision becomes final and conclusive, the protocol of subdivision becomes final and conclusive, it shall be deemed that one of co-owned land cannot be disputed by the aforementioned special procedure.

2. A. According to the reasoning of the judgment below, the court below acknowledged the facts as stated in its reasoning after comprehensively taking account of the adopted evidence, and determined that the defendant was in a position where the purchaser of each land and the defendant are liable to implement the procedure for the transfer of ownership based on the cancellation of mutual title trust since they were in a sectional co-ownership relationship with regard to co-owned land after dividing the land including the plaintiffs at the time of commencement of the procedure for partition under the Act on Special Cases Concerning the Settlement of Co-owned Land. However, the plaintiffs seems to have failed to understand the specific contents of the partition as stated in the protocol, and they could not be deemed the owner of the share even if the protocol of partition is finalized, and that the defendant who had no authority to do so cannot be deemed the owner of the share even if the protocol of partition is finalized, due to the reasons such as mistake in the process of the division and the substitute registration on December 4, 1986, and determined that the share of co-owned land was changed from 1,380 to 1,522.

B. However, the lower court’s determination is difficult to accept for the following reasons.

(2) The above 3/10 of the co-owner's share of 2/10 of the co-owner's share of 3/10 of the co-owner's share of 3/10 of the co-owner's share of 2/10 of the co-owner's share of 3/10 of the co-owner's share of 3/10 of the co-owner's share of 9/10 of the co-owner's share of 2/10 of the co-owner's share of 3/10 of the co-owner's share of 4/10 of the co-owner's share of 8/10 of the co-owner's share of 2/10 of the co-owner's share of 3/10 of the co-owner's share of 3/10 of the above co-owner's share of 9/6/10 of the non-party's share of 3/10 of the above co-owner's share of 4.

In light of the above legal principles and the above facts, it cannot be deemed that the defendant acquired a certain share of the land in this case by the protocol of subdivision finalized by the procedure of co-ownership under the Act on Special Cases without any legal cause. Moreover, the change of the part of the plaintiffs' share of the land in this case according to the increase in the area of land in the joint substitution process. The plaintiffs can easily expect that the land cannot be a sole owner, and there is no proof as to the invalidity of the defendant's share registration, and therefore, it cannot be deemed that the defendant owns a part of the land in this case ① and ②.

C. Nevertheless, the court below accepted the plaintiffs' claim based on the judgment that the defendant acquired part of the land ① and ② in the process of co-owned land partition without any legal cause. The court below erred by misapprehending the legal principles as to the validity of protocol of partition and unjust enrichment, which affected the conclusion of the judgment. The defendant's assertion pointing this out is with merit.

3. Therefore, the lower judgment is reversed, and the case is remanded to the lower court for a new trial and determination. It is so decided as per Disposition by the assent of all participating Justices on the bench.

Justices Lee Hong-hoon (Presiding Justice)