1. In principle, when an employer concludes a labor contract, the employer determines the basic wage for the employee and pays an aggregate by adding various allowances based on that determination.

(3) If an employer and an employee enter into a wage payment contract or collective agreement based on the so-called comprehensive wage system with the intent to pay a certain amount as legal allowances regardless of the number of working hours, without setting the basic wage in advance, as monthly wage or daily wage, or setting the basic wage in advance without setting the amount included in the statutory allowances, but without distinguishing the legal allowances, and at the same time setting the certain amount as statutory allowances, and without setting the number of working hours, it is valid when the employer and an employee enter into a wage payment contract or collective agreement based on the so-called comprehensive wage system with the intent to pay a certain amount as legal allowances.

Whether an agreement on the comprehensive wage system has been established shall be specifically determined by considering various circumstances, such as working hours, form and nature of work, unit for wage calculation, contents of collective agreement and rules of employment, and actual conditions of the same workplace in the same kind.

Although it is naturally expected that overtime, night, and holiday work are to be performed in each individual case, it does not constitute a comprehensive wage system if the collective agreement, rules of employment, benefits regulations, etc. stipulate that overtime, night, and holiday work allowances, etc. shall be paid separately from the basic pay separately from the basic pay.

In addition, there is an agreement on overtime working hours exceeding certain working hours in a collective agreement, etc.

Inasmuch as there is an agreement on the comprehensive wage system as above on the grounds that the rate of increase in wages was set based on the amount including allowances or basic pay, it cannot be readily concluded.

2.(a)

In light of these legal principles, the reasoning of the lower judgment.