The judgment of the court below is reversed.

The first instance judgment is revoked, and all of the instant lawsuits are dismissed.

The total cost of the lawsuit shall be the cost of the lawsuit.

Judgment ex officio is made.

1. “The benefit of confirmation” in a lawsuit for confirmation is recognized when there is a danger in existence in a party’s rights or legal status, and it is the most effective and appropriate means to obtain a judgment for confirmation in removal thereof (see, e.g., Supreme Court Decision 91Da1264, Oct. 11, 1991). 2. The Plaintiffs asserted the following as follows, and filed the instant lawsuit seeking confirmation that the part of the incidental agreement entered into between A and B Trade Union, including the Plaintiffs, is invalid, unlike the retirement age of other employees (see, e.g., Supreme Court Decision 91Da1264, May 31, 201).

On December 17, 2013, the Defendant and the B Trade Union agreed to extend the retirement age on December 17, 2013, but unlike the retirement age of the employees born after 1958, the retirement age of the 1955 students was one year, the retirement age of the 1956 students was one year and six months, and the retirement age of the 1957 students was extended by two years.

B. As above, setting the retirement age differently by the employees is null and void in violation of the equal rights under the Constitution, or each provision prohibiting discrimination, such as the Act on Prohibition of Age Discrimination in Employment and Elderly Employment Promotion (hereinafter “the Elderly Employment Promotion Act”).

However, even if it is not so, the 1956 life portion is invalid in violation of Article 19 of the Elderly Employment Act, which stipulates that the retirement age shall be at least 60 years after its enforcement on January 1, 2016.

C. Therefore, the retirement date of the Plaintiffs, who are the employees born during the second half of 1956, should be deemed as December 31, 2016, when the Plaintiffs reached the age of 60 according to the Defendant’s revised personnel regulations and its enforcement regulations.

3. According to the above plaintiffs' assertion, the retirement date of the plaintiffs' assertion has already lapsed, and it is currently the plaintiffs' existing right to seek nullification of the retirement age portion among the incidental agreements concluded on December 17, 2013.