1. The former Act on the Maintenance and Improvement of Urban Areas and Dwelling Conditions for Residents (amended by Act No. 8785, Dec. 21, 2007; hereinafter the same shall apply) provides for the matters to be included in the articles of association in consideration of the fact that the “expenses of a cooperative” or the “matters to be included in the contract for the selection of a work executor or designer and the cost-bearing of the association members” have a significant impact on the members’ share of expenses (Article 20(1)8 and 15). Therefore, it is reasonable to readily recognize the contents of the amended articles of association that should require the consent of at least 2/3 of the association members to modify the contents of the amended articles of association to be necessary for the amendment of the articles of association to be strictly stated in the articles of association, or the contents to be included in the contract for the selection and contract of a work executor or designer, as it is substantially modified to the extent that the interests of the association members can be substantially affected by the initial resolution of re-building association, as well as the contents of the amended articles of association or resolution.

2. According to the reasoning of the lower judgment and evidence duly admitted by the lower court, ① the number of members of the Defendant Cooperative was 16 to 40, 25 square meters of the ground with respect to “design outlines of new construction”: 1,562 units, 38 square units: 2,63 units, 47 square units: 60 units, 50 square units: 47 square units, 50 square units: 138 units, 64 square units, 64 square units, 35 square units, 27 square units, and 250 square units, and 40 square units, and 250 square units, 26 percent of the total number of members of the Plaintiff’s new construction; 30 percent of the number of members of the Plaintiff’s new construction; 45 square units, 276 square units, 250 percent of the total number of members of the Plaintiff’s new construction; 264 square units, and 96 percent of the building’s average floor area ratio.

Examining these facts in light of the above legal principles, since the project implementation plan of this case actually changes to the extent that the "expenses of the association" or "matters to be included in the contract" has a significant impact on the interests of the association members compared to the time of the initial rebuilding resolution, it requires the consent of at least 2/3 of the association members by analogy of the amendment procedure requiring special multiple consent requirements. Therefore, the project implementation plan of this case cannot be deemed lawful solely on the fact that the project implementation plan of this case satisfies the requirements for the quorum under the articles of association of the defendant association, and it is incomplete that the project implementation plan

However, at the time of the establishment of the instant project implementation plan, the legal principles on the requirements for resolution in the case of substantial change in the design outline, etc. of newly constructed apartment compared with the time of the reconstruction resolution were not clearly presented by the Supreme Court decision, etc. Therefore, it is difficult to view that the defects that did not obtain the consent of at least 2/3 of the members of the

3. The court below rejected the main claim seeking the invalidation of the project execution plan of this case and the preliminary claim seeking its revocation since the project execution plan of this case does not fall under the amendment of the articles of association that requires the consent of at least two-thirds of the members of the association since it does not require the consent of at least two-thirds of the members of the association. The court below erred in the misapprehension of legal principles as to the requirements for the consent of the project execution plan of this case under the former Act on the Maintenance and Improvement of Urban Areas and Dwelling Conditions for Residents, but it cannot be viewed as objectively obvious that the defects that have not obtained at least two-thirds of members of the association cannot be the ground for invalidation of the project execution plan of this case. Thus, the court below's decision on the main claim seeking the invalidation

4. Therefore, without further proceeding to decide on the remaining grounds of appeal, the part concerning the conjunctive claim among the judgment below is reversed, and that part of the judgment below is remanded to the court below for further proceedings consistent with this Opinion. The appeal on the plaintiffs' primary claim is all dismissed. It is so decided as per Disposition by the assent of

Justices Kim Shin (Presiding Justice)