1. The plaintiff's claim is dismissed.

2. The costs of lawsuit shall be borne by the Plaintiff, including the part resulting from the supplementary participation.

1. Causes and contents of the decision in the retrial;

A. A school juristic person B (hereinafter “instant juristic person”) is a juristic person that establishes and operates educational institutions, such as C University.

A Hospital is an affiliated organization of the C University established by the instant corporation, and is in charge of the operation of the C University’s health and medical education institutions and affiliated hospitals, using approximately six thousand full-time workers.

A Hospital shall negotiate with a trade union as a separate negotiating unit from the corporation of this case and conclude a collective agreement.

B. The Plaintiff is a company-level trade union organized for workers belonging to A Hospital on February 9, 1963, and approximately 3,660 workers belonging to A Hospital are working for the Plaintiff.

The Intervenor joining the Defendant (hereinafter referred to as the “ Intervenor”) is an enterprise-level trade union organized for workers belonging to the A Hospital on March 16, 2017, and approximately 270 workers belonging to the A Hospital join the Intervenor.

C. On May 29, 2017, A Hospital, the Plaintiff, and the Intervenor determined the Plaintiff as a representative bargaining trade union through the process of simplification of bargaining windows pursuant to Article 29-2 of the Trade Union and Labor Relations Adjustment Act (hereinafter “Trade Union Act”).

On August 31, 2017, the Plaintiff, a representative bargaining trade union, entered into a collective agreement in 2017 with the term of validity from August 31, 2017 to February 28, 2019 (hereinafter “instant collective agreement”) (hereinafter “instant collective agreement”), and the contents relating to the instant case are as follows.

Article 12 (Full-time Officer of the Cooperative) ① Recognizing the limit of exemption from working hours as 14,00 hours a year, the Cooperative shall use at least 11 persons (including its full-time officer) and shall notify the Medical Center of its list.

The collective agreement in 2015, which is the previous collective agreement, provided the same content.

E. The Plaintiff used 14,00 hours per year, which is the limit of statutory working hours exemption according to the size of its members, before the Intervenor was established.

On March 31, 2017, the Plaintiff, at A Hospital, has seven new executives, such as D chairperson, etc. working hours.