A. The Defendant is an intervenor’s subsidiary that was incorporated on December 30, 2008 by the Seoul Metropolitan Government Urban Railroad Corporation (the Seoul Urban Railroad Corporation was merged on May 31, 2017; hereinafter “ Intervenor”) as part of restructuring.

The intervenor entrusted the defendant with the maintenance of electric trains and the repair of tracks among the duties operated in the form of direct management.

B. On March 2009, the Intervenor entered into an agreement with the Defendant on the wages and employment guarantee (hereinafter “instant agreement”) with the Defendant in order to reduce the number of human resources through the method of voluntary retirement, and guarantee the wage level received from the Intervenor.

The instant Convention provides that “The Defendant shall preferentially employ the retired person arising from the efficient management of human resources after the reorganization of the organization, and the Defendant shall extend the retirement age of the person who voluntarily retired for three years after the retirement age of the original intervenor, and apply it to the retirement age of the intervenor (Article 7), and the remuneration of the person who voluntarily retired shall be paid in accordance with the Defendant’s remuneration regulations, and the remuneration of the Intervenor shall be paid separately by the Intervenor after compensating the difference of the remuneration in accordance with the Intervenor’s remuneration regulations and the annual salary regulations, and the amount of the preservation shall be paid after deducting the desired retirement allowance in proportion

C. Article 3 of the Defendant’s Remuneration Regulations provides that “The monthly amount of ordinary wages refers to the annual salary, the monthly amount of the annual salary refers to the amount calculated by dividing the basic annual salary by 12 months, and the basic annual salary refers to the basic annual salary by class in attached Table 1 in cases of a person who voluntarily retires, and means the amount calculated by multiplying the basic salary by 12 months by the basic salary by class in attached Table

Meanwhile, Article 2 of the Addenda to the Rules on Remuneration of the Defendant reflects the instant agreement, the remuneration for the employee employed by the Defendant, who is desired to retire from the Intervenor due to the efficient operation of human resources, shall be preserved for the level of wages before retirement, but the honorary retirement allowances paid by the Intervenor shall be divided