The judgment below is reversed and the case is remanded to Seoul High Court.

The grounds of appeal are examined.

1. In the case of taxes on the method of return and payment, such as registration tax, in principle, a taxpayer shall, by fixing the tax base and the amount of tax, specifically determine the tax liability by his act of filing a return, and the act of payment shall be the performance of specific tax liability fixed by the return, and the local government shall hold the

Therefore, unless a person liable for duty payment's filing of a report is void as a matter of course due to a significant and apparent defect, it shall not be deemed as unjust enrichment. Here, as to whether the defect in the filing of a report falls under the invalidation as a matter of course due to a significant and apparent defect, the purpose, meaning, function, and legal remedies for the defective filing of a report should be considered as a basis for the filing of the report, and the specific circumstances caused by the filing of the report should be

(see, e.g., Supreme Court Decisions 94Da60363, Dec. 5, 1995; 2006Da81257, Apr. 23, 2009). Meanwhile, a taxation summary relating to a tax obligation by means of tax return is required.

In the absence of clear legal basis as to whether the provisions of Acts and subordinate statutes on the cases of tax reduction and exemption, etc. apply to specific legal relations or factual relations, the tax authority has interpreted and operated one of them, and the taxpayer has paid the tax base and the tax amount in accordance with the interpretation thereof. Even if the interpretation of the tax authority was found to have been erroneous later, the taxpayer’s return and payment cannot be deemed to be null and void as long as it is recognized that there is a reasonable ground for the interpretation thereof.

(Supreme Court Decision 2012Da23382 Decided January 16, 2014). 2. The lower court established on May 23, 2006 by the Ministry of the Interior.