The costs of appeal are assessed against the Defendant (Counterclaim Plaintiff).

1. Regarding ground of appeal No. 1

A. Article 4 of the Enforcement Decree of the Act on Contracts to Which the State is a Party (hereinafter “State Contract Act”) provides that “A contracting officer shall not make any special agreement or set conditions unreasonably restricting the contractual interests of the other party under the State Contracts Act and the Decree of the relevant Acts and subordinate statutes when entering into a contract.” Thus, a special agreement that unfairly limits the contractual interests of the other party to a contract to which the State is

Here, a special contract is unreasonably limited to the contractual interests of the other party, and it is not sufficient that the special contract is somewhat disadvantageous to the other party to the contract in order to deem it invalid in violation of Article 4 of the Enforcement Decree of the State Contracts Act. It should be recognized that the State abused its position in the transaction and unfairly puts disadvantage to the other party to the transaction by prescribing special agreement contrary to

In addition, whether a special contract unfairly limits the contractual interests of a trader should be determined by considering all the circumstances such as the content of disadvantage and the probability of disadvantage that may arise to a trader, the impact on the transaction process between the parties, and the provisions of relevant laws and regulations.

Meanwhile, according to Article 65(3)3 of the Enforcement Decree of the State Contracts Act, where the Government requests a change of design (including a case where the contractor is not responsible for the change of design), the unit price of increased quantity shall be determined by mutual consultation among the parties within the scope of an amount calculated by multiplying the unit price and its unit price as at the time of the change of design by the successful bid rate (hereinafter “consultation rate”), and where no agreement is reached, it shall be calculated as at the time of