8.8 Appellate review
8.8.1 Appellate-level courts
A party in a civil infringement action involving patent or other listed IP rights may appeal the decision of the district court to the Patent Court. Other IP infringement cases generally must be appealed to one of the high courts (or to an appellate panel of the district court in some cases).170 Unless dismissed on procedural grounds, appellate proceedings are conducted on a substantially de novo basis. In other words, while the appellate court will generally rely heavily on the record of the lower court, it is typical for the court to admit new evidence and arguments from the parties.
If a party requests to introduce new evidence in the appellate proceeding, the party must provide a detailed explanation for the failure to submit the evidence in the lower court. The court will then determine whether to admit the evidence in consideration of the circumstances, including whether significant harm to the other party is expected from a delay in court proceedings or whether an expedited proceeding is necessary.171
Unlike in the court of first instance, where hearings are often held multiple times, the appellate court usually closes the hearing after the first issue-by-issue review unless a new piece of evidence is introduced. In most cases, each party holds a technology review session explaining the technology from its viewpoint, followed by oral arguments for about 20 minutes.172 After both parties have presented their cases, the judicial panel asks questions by issue.173
When an infringement case and a revocation case of IPTAB decision involving the same patent or other listed IP rights are pending concurrently before the same judicial panel and are litigated by the same parties, and when the need for parallel hearing is recognized, the court will, in principle, hold the trial on both cases in parallel.174
The appellate court will generally try to render a decision within six months to one year from the filing of the appeal. However, this timeframe may be significantly longer for complex cases.
8.8.2 Supreme Court
A decision by the appellate court may be appealed to the Supreme Court (the highest court in the Republic of Korea). The Supreme Court generally only hears cases dealing with legal issues of material importance, such as legal issues of first impression. Otherwise, the appeal will be summarily dismissed without a review of the merits of the case, typically within four months from the date of transfer of litigation records to the Supreme Court.
If the case is accepted for substantive review, the Supreme Court will decide the case in view of the evidence presented to the lower courts and will typically render a decision within one to two years from the date of appeal. These appeals are usually handled by a panel of four justices. However, the Supreme Court may choose to review the appeal en banc when the usual four-justice panel seems insufficient, such as when there is a need to overrule precedents.