1. The plaintiffs' appeal and the preliminary claims added in the trial are all dismissed.

2. After an appeal is filed.

1. Facts of recognition;

A. The parties concerned are public corporations established in accordance with the Ordinance on the Establishment and Operation of Local Public Enterprises Act and the Seoul Metropolitan Government Ordinance on the Establishment and Operation of the Seoul Metropolitan Government, whose business purpose is the construction and operation of subway 1 through 4, and the Seoul Metropolitan Railway Corporation Trade Union is the defendant's trade

(hereinafter “Non-Party Partnership.” The Plaintiffs, as employees of the Defendant in 1955, were retired on December 31, 2014 on the premise that the retirement age was 59 years of age, as seen below.

B. (i) The retirement age of Defendant’s employees was originally 60 years of age, but around December 2000, the retirement age was reduced to 58 years of age through the conclusion of collective agreements and the amendment of personnel regulations (Article 32) between the Defendant and the Non-Party Partnership.

The Defendant and the Nonparty Union agreed to the principle that “the extension of the retirement age shall be promoted in conjunction with the extension of the retirement age of public officials in the future,” on several occasions in the course of concluding the collective agreement of December 31, 2003, the collective agreement of January 30, 2007, the collective agreement of November 2007, and the collective agreement of November 20, 2008, and the collective agreement of November 2008.” On June 13, 2008 and December 31, 2008, the retirement age of public officials was changed to 60 years.

However, there was no change in the content that the provision regarding the extension of retirement age under a collective agreement concluded on December 22, 2010 between the defendant and the non-party union, stating that “the extension of retirement age shall be linked to the extension of retirement age for public officials in the future.

1.The extension of retirement age and retirement allowances shall be as follows:

The extension of retirement age shall be implemented as public officials.

(b) Matters concerning the extension of retirement age and the short-term retirement allowance system (retirement allowances) shall be implemented during the first half of 2013 by preparing a detailed implementation plan in the working subcommittee of the Seoul Model Council;

On the other hand, from 2011, the issue of extending the retirement age of the defendant's employees was discussed. The defendant and the non-party union are about the extension of retirement age on December 10, 2012.