1. The plaintiffs' claims are dismissed.

2. The costs of lawsuit are assessed against the plaintiffs.

1. Basic facts

A. Nonparty Korea National Housing Corporation publicly announced the construction of an integrated energy facility in the Asan-gu Seoul National Housing Corporation (hereinafter “instant construction”), but only Plaintiff Gyeongnam Enterprise Co., Ltd. (hereinafter “Plaintiff Gyeongnam Enterprise”) would undertake the instant construction work by a private contract upon complying with the bidding. On January 26, 2007, Nonparty 2 notified Plaintiff Gyeongnam Enterprise that the construction was determined as the person qualified for design.

B. On April 16, 2007, the Plaintiffs constituted a joint supply and demand organization (70% of the shares in the Plaintiff Honam Enterprise, and 30% of the shares in the Plaintiff Barun Construction Co., Ltd.) and entered into a contract with the Korea National Housing Corporation to receive a contract for the instant construction project from April 19, 2007 to January 17, 201 (hereinafter “instant contract”). The terms and conditions of the construction contract, general conditions of the construction contract, and special conditions of the construction contract (Ⅱ), included in the contents of the said contract, stipulate as follows, regarding the adjustment of the contract amount due to price fluctuation:

[General Conditions of Contract for Construction Project] The adjustment of the contract amount due to price fluctuation in Article 22 ① The adjustment of the contract amount due to price fluctuation shall be governed by Article 64 of the Enforcement Decree of the Act on Contracts to Which the State is a Party and Article 74 of

(3) Where the contract amount is increased under the provisions of paragraph (1), it shall be requested by the other party, and (5) Where the Korea National Housing Corporation increases the contract amount under the provisions of paragraphs (1) through (4), it shall adjust the contract amount within 30 days from the date it receives a request from the other party.

(Ⅱ) [Attachment] Except for the application of price fluctuation in Article 15 of the Special Conditions for Construction Contract (Ⅱ] ① The contractor shall provide bid price for the amount related to the overseas supply of the materials to be purchased (the total amount of contracts with the overseas enterprises of the same item as material cost, reserve products, royalties, insurance premiums, etc.).