The part against the plaintiff is reversed, and that part of the case is remanded to the Seoul High Court.

1. As to the grounds of appeal on the omitted income

(a) Summary of taxation in a lawsuit seeking the revocation of a tax imposition disposition;

Inasmuch as the tax authority bears the burden of proving the facts, the taxpayer's account of the financial institution constitutes sales or revenue, and the taxpayer's account is the omitted amount in the report.

It is the principle that tax authorities should prove the facts.

However, the taxpayer’s account of a financial institution may be proved by either disclosing or revealing indirect facts that can be inferred in light of the empirical rule in the course of a specific lawsuit (see, e.g., Supreme Court Decision 2003Du14284, Apr. 27, 2004). In such cases, whether such presumption can be determined by comprehensively taking account of various circumstances as to whether the relevant financial institution’s account was used as a principal deposit management account concerning sales or revenues subject to taxation, the date of deposit, the other party, and the amount, etc., whether the relevant financial institution has a appearance of sales or revenues, the proportion of transactions related to sales or revenues among the account’s transactions, the possibility of mixing funds for other purposes than sales or revenues, and the degree thereof.

In addition, even if the account of a taxpayer’s financial institution as a principal deposit management account for sales or revenues can be presumed to constitute sales or revenues as a result of comprehensive calculation of the above various circumstances, individual deposits or certain types of deposits are identical to sales or revenues already reported in light of the empirical rule as well as the date, amount, transaction counterpart, and circumstances.