무효행위의 전환인가, 보충적 해석인가? -대법원 2016. 11. 18. 선고 2013다42236 전원합의체 판결

The majority opinion of the plenary decision of the Korean Supreme Court, dated November 18, 2016 acknowledged the conversion of the invalid juristic act into the effective juristic act based on Article 138 of the Korean Civil Code. In this case, the leaser of the public lease house set the deposit money higher than the standard deposit money and the monthly rent lower than the standard monthly rent. The standard deposit money and monthly rent were both stiplulated in the relevant statute, and the consent of the leasee was required, by the same statute, to make changes to the amount of deposit money and/or monthly rent. The lack of leasee’s consent rendered the lease contract invalid. The Supreme Court declared that the lease contract is still valid in so far as the deposit money is reduced as the standard deposit money and the monthly rent is increased as the standard monthly rent, based on the rule of the conversion of the invalid juristic act. I agree with the conclusion that the majority opinion reached. However, the rule of the conversion of the invalid juristic act cannot be the basis of this decision, as there was no consensus between the parties regarding the standard monthly rent that is higher than the agreed monthly rent. This result can be justified by the gap-filling by the court based on the hypothetical intent of the parties. The economic value of the agreed deposit money and monthly rent is almost equivalent to that of the standard deposit money and monthly rent. So increasing the monthly rent as high as the standard monthly rent and reducing the deposit money as low as the standard deposit at the same time is not disadvantageous to the lessee. Such arrangement accords the hypothetical intent of the parties and is not contrary to the balance of the interest.