All appeals are dismissed.

The costs of appeal are assessed against the defendant supplementary intervenor.

The grounds of appeal are examined (to the extent of supplement in case of supplemental appellate briefs not timely filed).

1. The facts found by the court below are as follows. A.

The defendant partnership was authorized to establish a partnership on July 28, 2009 and was registered on August 4, 2009, and 827 members of the redevelopment project association were 827 members.

On May 15, 2010, the Defendant Cooperative selected the Intervenor (Written Voting 200, On-the-spot Voting 202) as the developer of the instant redevelopment project, among the participants (Written Voting 67, On-the-spot Voting 264) and Hyundai Construction Co., Ltd. (hereinafter “On-the-spot Construction”) who participated in the tender of the contractor by holding a general meeting of the partnership and received a majority of the participants (Written Voting 67, On-the-spot Voting 264).

(hereinafter referred to as “the instant decision to select the contractor”). B

At the resolution of the selection of the contractor of this case, the Intervenor solicited the Defendant’s members to purchase money, valuables, or entertainment in order to allow some employees of the Intervenor to be selected as the contractor. Before the decision of the contractor’s selection, the Plaintiff offered the members of the Plaintiff a cash of KRW 1 million in return for advance payment to the Intervenor, or offered the members of the Plaintiff a special-level hotel, hotel, lodging, public performance of a well-known person, and entertainment such as Busan Tourism.

Some of the intervenor's employees were indicted for interference with bidding and convicted of such act (Seoul Western District Court Decision 2015No26 decided April 10, 2015), and the conviction was finalized as it is.

C. On May 26, 2012, the Defendant Union held a general meeting of shareholders on 431 votes (including 366 votes in writing, 65 votes, and 399 votes in writing). Dissenting 23 votes (including 6 votes in writing, 17 votes in the field, 32 votes in the lower judgment, and 25 votes in the field) of the Defendant Union and the Intervenor’s “Contract for Construction Work”.