All appeals are dismissed.

The costs of appeal are assessed against the Defendant’s Intervenor, and the remainder.

The grounds of appeal are examined (to the extent of supplement in case of supplemental appellate briefs not timely filed by the intervenor).

In the case of a worker who entered into an employment contract with a fixed period of time, the status relationship as an employee shall be terminated naturally, and if the employment contract is not renewed, the worker shall retire automatically even if there is no declaration of refusal to renew the employment contract.

However, in a case where a labor contract, employment rules, or collective agreement provides that even if the term expires, if certain requirements are met, the pertinent labor contract shall be renewed if such requirements are met. In full view of various circumstances surrounding the pertinent labor contract such as the contents of the labor contract and the motive and circumstances leading up to the formation of the contract, the standards for renewal of the contract, etc., whether or not to establish the requirements or procedures for renewal of the contract, the status thereof, and the contents of the work performed by the employee, etc., in a case where there is a trust between the parties to the labor contract that the contract is renewed if certain requirements are met, and the right to expect that the contract may be renewed accordingly, the employer's refusal of the contract unfairly in violation of such provision has no effect as unfair, and in this case, the labor relationship after the expiration

(see, e.g., Supreme Court Decisions 2007Du1729, Apr. 14, 201; 201Du12528, Feb. 13, 2014). In addition, “Act on the Protection, etc. of Fixed-Term and Part-Time Workers (hereinafter “ Fixed-Term Act”)” is deemed to have concluded an employment contract without a fixed period of time where a fixed-term worker is employed for more than two years, unless there are grounds for exception under the proviso to Article 4(1) of the same Act. However, the legislative purport of the Fixed-Term Act is to stipulate the said Act.