1. The plaintiff's appeal is dismissed.

2. The costs of appeal shall be borne by the Plaintiff.

The purport of the claim and appeal is the purport of the appeal.

1. Basic facts

A. The Defendant served for the Plaintiff Company from November 25, 201 to May 11, 2015.

The plaintiff did not withhold four major insurance premiums, such as national pension premiums, health care premiums, employment insurance premiums, etc., which should be withheld from the defendant's salary during the period of service of the defendant.

B. On February 3, 2017, the Defendant filed a petition with the head of the Seoul Eastern District Office by asserting that he/she did not receive retirement allowances, and received confirmation from the head of the Seoul East District Office on February 6, 2017 that the Plaintiff delayed payment of retirement allowances of KRW 9,455,191 to the Defendant.

[Ground of recognition] Unsatisfy, entry of Gap evidence 2, purport of whole pleadings

2. The gist of the Plaintiff’s assertion and the Defendant promised, instead of giving the Defendant a retirement allowance, to bear the Plaintiff’s four premium to be withheld from the Defendant’s pay.

Therefore, even though the plaintiff paid the four major insurance premiums by the defendant, the defendant asserted that he did not receive retirement allowances and received the delayed payment of retirement allowances amounting to KRW 9,455,191 from the head of the Seoul East District Office.

Thus, the defendant has a duty to return the amount of income tax withheld at source to the plaintiff as unjust enrichment, since he obtained a total of KRW 7,949,520 without any legal ground.

3. The written evidence No. 3 alone is insufficient to acknowledge that the Plaintiff and the Defendant entered into an agreement with the Plaintiff to pay the four major premiums on the condition that the Plaintiff would pay the unpaid retirement allowances, and there is no other evidence to acknowledge it.

Even if not,

Even if the Defendant did not claim retirement allowances to the Plaintiff upon retirement, it is invalid in violation of the Labor Standards Act and the Guarantee of Workers' Retirement Benefits Act, which are mandatory laws.

(see, e.g., Supreme Court Decision 2000Da27671, Jul. 26, 2002). And waiver of a retirement allowance claim in advance.