The costs of appeal are assessed against the Defendant. The costs of appeal are assessed against the Plaintiff.

1. As to the Defendant’s grounds of appeal, this case is a small-sum case to which the Trial of Small Claims Act applies, and thus, an appeal may be filed with the Supreme Court only when there are grounds prescribed in Article 3

The defendant's ground of appeal does not fall under any of the above provisions, and thus cannot be a legitimate ground of appeal.

2. Appellee concerning the Plaintiff’s ground of incidental appeal may be made even after the right to appeal is extinguished, but it is necessary to file an appeal within the period for submitting the appellate brief and to submit a statement of reasons therefor (see, e.g., Supreme Court Decision 9Da50538, Jan. 21, 2000). According to the records, the Plaintiff submitted an additional appeal within 20 days from the date on which the notice of receipt of the record of appeal was served to the Defendant who is the appellant, but the Plaintiff did not state the ground of incidental appeal in the annexed appellate brief, and it is obvious that the supplementary appellate brief was submitted only after 20 days from the date on which the notice of receipt of the record of the appeal was served. Thus, the incidental appeal in this case is a case where the appellate brief

3. Therefore, all appeals and supplementary appeals are dismissed, and the costs of appeal are assessed against the defendant and the costs of appeal are assessed against the plaintiff. It is so decided as per Disposition by the assent of all participating Justices on the bench.