A. On January 17, 2017, the Plaintiff was a limited liability company established pursuant to the laws of the United States of America (hereinafter “U.S.”), and entered into a contract with B Co., Ltd. (hereinafter “B”), a domestic corporation, under which the Plaintiff granted B the right to use the patent related to the MIMF (hereinafter “instant patent”) (hereinafter “the instant patent”). In return, the Plaintiff entered into the contract (hereinafter “instant contract”).

B. The patent license agreement entered into between the Plaintiff and B at the time of entering into the instant contract (hereinafter “instant contract”) states that “the patent of this case refers to all patents and patent applications owned, owned, or controlled in the present or future by the Plaintiff, including the patents specified in the AA and the rights related thereto,” and the patents described in the AA are 12 patents registered in each of the world countries, including the United States, and they are not registered in the Republic of Korea.”

C. On January 31, 2017, B deemed that the instant royalty constitutes a domestic source income subject to withholding, and thus, B applied the limited tax rate of 15% under Article 14(1) of the Convention between the Republic of Korea and the United States of America for the Avoidance of Double Taxation and the Prevention of Fiscal Evasion with respect to Taxes on Income and the Encouragement of International Trade and Investment (hereinafter “Korea-U.S. Tax Convention”), and paid to the Defendant through withholding KRW 451,542,000 equivalent to USD 390,000.

On April 11, 2017, the Plaintiff filed a claim for correction with the purport that the Plaintiff should refund all the withheld tax amount to the Plaintiff with respect to the instant royalty, while the instant royalty to the Defendant is merely the price for the use of patent rights not registered in Korea, not the source income subject to withholding. However, the Defendant is the Corporate Tax Act on June 7, 2017.