The judgment below is reversed and the case is remanded to Seoul High Court.

The grounds of appeal are examined.

1. Regarding ground of appeal No. 1

A. The overall contract for long-term continuing construction is not based on the conclusive agreement on the total construction cost or the total construction period, but rather linked according to the conclusion of each annual contract.

In general, the parties to a long-term continuing construction contract appear to have the intention to utilize the total construction cost and total construction period of each annual contract as a provisional standard in concluding each annual contract. The total construction cost and total construction period stated in each annual contract are not considered to have the intention to generate conclusive rights and obligations or to have binding force on the construction cost and construction period.

In other words, the so-called "long-term long-term continuing construction contract" should be regarded as an agreement on the fact that the contracting party is in the position of concluding each annual contract and that the total scale of the contract is based on the overall contract as the criteria for the temporary utilization of the overall scale of project, construction amount, construction period

Therefore, the validity of the overall contract is limited to the determination of the contracting party, the determination of the intention of performing the contract, the contract price, etc., and it should be deemed that the specific contents of the performance, the scope of the contract price to be paid to the contracting party, the execution period of the contract, etc

(see Supreme Court en banc Decision 2014Da235189 Decided October 30, 2018). B.

Nevertheless, under the premise that the overall contract concluded with respect to the total construction period and the total construction price is binding separately between the parties to the contract, and the total construction price under the overall contract is the total construction cost including indirect construction cost during the total construction period, the lower court is separate from the annual contract in a long-term continuing construction contract.