An International Guide to
Patent Case Management for Judges

8.4 Patent invalidity

8.4.1 Revocation cases

Revocation actions refer to those seeking judicial review and subsequent revocation of IPTAB decisions. The IPTAB decides on the invalidity of patent registration, confirms the scope of patent rights and reviews the examiners’ rejections of patent applications. Given that IPTAB decisions are administrative dispositions and that revocation actions are administrative lawsuits filed to contest such dispositions, the Administrative Procedure Act is applicable to revocation actions, and the Civil Procedure Act also applies mutatis mutandis to those actions pursuant to Article 8(2) of the Administrative Procedure Act.³⁴

8.4.1.1 Territorial jurisdiction

While Article 8(1) of the Administrative Procedure Act stipulates that “[e]xcept as otherwise provided for in other Acts, administrative suits shall be governed by this Act,” Article 186(1) of the Patent Act sets forth that the Patent Court has exclusive jurisdiction over revocation actions.³⁵ Revocation actions were the only type of cases that fell under the exclusive jurisdiction of the Patent Court before the jurisdictional concentration.

8.4.1.2 Jurisdiction by court level

The Patent Court’s decision on a revocation case may be appealed to the Supreme Court (Article 186(8) of the Patent Act). In the Patent Act and other applicable laws, there is no special provision regarding the appeal procedure, so the procedures in general civil actions apply mutatis mutandis to the appeals in revocation cases (Article 8(2) of the Administrative Procedure Act).

8.4.2 Administrative patent lawsuits

Administrative litigation, as a type of judicial process, is a procedure wherein a court judges a dispute over legal relations under public law. Administrative litigation associated with patents is classified into (i) legal proceedings seeking the revocation of decisions rendered by the IPTAB as prescribed in Article 186 of the Patent Act, (ii) administrative lawsuits against administrative dispositions (other than the IPTAB decisions) imposed by the government or the Commissioner of the KIPO,³⁶ and (iii) legal proceedings against IPTAB decisions, rulings or adjudications on compensation or considerations prescribed in Article 190 of the Patent Act.³⁷ For administrative litigation falling under the first category, the Patent Court has exclusive jurisdiction. For administrative litigation falling under the second and third categories, the administrative court with jurisdiction over the location of the defendant’s administrative agency, or the Seoul Administrative Court, has jurisdiction pursuant to Article 9 of the Administrative Litigation Act. Accordingly, legal proceedings against dispositions of the Korea Trade Commission, which serves the equivalent role as the United States International Trade Commission, should also be filed with the Seoul Administrative Court or any other competent court, not with the Patent Court. Administrative litigation falling under the first category always requires the IPTAB’s decision before lodging a lawsuit with the Patent Court.³⁸ However, administrative litigation falling under the other two categories may be instituted without going through the adjudication process.³⁹

Among the three types of administrative litigation concerning patents, legal proceedings falling under the first category – namely, litigation for the revocation of IPTAB decisions, or revocation suits – are most frequently used to contest the invalidation of patents. Thus, in the following paragraphs, we focus only on revocation suits.

8.4.2.1 Characteristics of revocation suits and applicable laws

As explained above, litigation for the revocation of IPTAB decisions is a type of administrative litigation, filed against dispositions or omissions of an administrative agency as prescribed in Article 3(i) of the Administrative Litigation Act. The Supreme Court has ruled that appeals suits include ex parte cases filed against the Commissioner of the KIPO and inter partes cases filed against patent holders or parties interested.⁴⁰

The Patent Act is first applicable to revocation suits. For matters not prescribed in the Patent Act, the provisions of the Administrative Litigation Act apply mutatis mutandis because lawsuits seeking the revocation of IPTAB decisions basically have the characteristics of administrative litigation. At the same time, matters not specifically stipulated in the Administrative Litigation Act are governed by the Civil Procedure Act.⁴¹ Therefore, the litigation and evidence collection procedures explained later in Section 8.6 are also generally applicable to revocation suits.

8.4.2.2 Scope of revocation suits

For appeals suits in general, a revocation suit can only be filed against the original disposition (namely, the principle of original dispositions), with the exception of cases where the adjudication itself is legally flawed (namely, the principle of exceptional adjudication).⁴² It should be noted that the Patent Act only allows the filing of a suit against the adjudication on an administrative appeal when it comes to litigation for the revocation of IPTAB decisions.⁴³ A decision to reject a patent application or to allow patent registration cannot be the subject matter of a revocation suit. If the applicant opposes any such decision, they must go through the IPTAB trial process before filing a suit against the IPTAB decision. Accordingly, the plaintiff must state in the complaint that their demand is to “revoke the decision of the IPTAB rendered on [date] with respect to [administrative trial case number],” not as “[patent number] shall become null and void.”

8.4.2.3 Litigants to a revocation suit

In ordinary administrative litigation, a person with legal interests to seek revocation of a disposition has the standing to sue⁴⁴ so that the person subject to the disposition or a third party all have standing as the plaintiff. However, a revocation suit may only be instituted by a party to the IPTAB trial, an intervenor in the IPTAB trial or a person who sought to intervene in the IPTAB trial but was denied.⁴⁵

In ex parte revocation suits, such as those concerning an examiner’s rejection, the Commissioner of the KIPO is named as the defendant. However, in inter partes revocation suits seeking invalidation of patents or confirmation of the scope of patent rights, the petitioners or respondents in the IPTAB proceeding have standing as the defendant.⁴⁶ In other words, in an inter partes revocation suit, the party who has received an unfavorable ruling in the inter partes administrative proceeding becomes the plaintiff, and the other party becomes the defendant. In a revocation suit against an IPTAB decision affirming the petitioner’s request, the petitioner is named as the defendant. If the petitioner’s request was denied at the IPTAB, the defendant in the revocation suit is the respondent in the IPTAB proceeding.

8.4.2.4 Period of filing a revocation suit

A revocation suit must be filed within 30 days from the date when a certified copy of the relevant IPTAB decision or ruling was served.⁴⁷ Any revocation suit filed after this period is considered unlawful and is dismissed.⁴⁸ The 30-day period can never be extended or shortened by the court, unlike other adjustable periods.⁴⁹ However, the presiding judge of the IPTAB may, ex officio, grant an additional period for the benefit of a person living in a remote area or in an area with poor access to transportation.⁵⁰ In practice, an additional period of 20 to 30 days is granted to foreigners overseas. Where the presiding judge of the IPTAB grants an additional period after the lapse of the initial 30 days, the revocation suit will still be dismissed because of the lapse of the initial period even if the application for extension had been filed with the IPTAB prior to the lapse of the initial period.⁵¹

8.4.2.5 Scope of examination in a revocation suit

According to the majority view and judicial precedent, the subject matter of a revocation suit is usually the unlawfulness of a disposition.⁵² Thus, the unlawfulness objectively present at the time of disposition, in any facet of the administrative disposition, including the procedure and elements thereof, becomes the subject matter of a revocation suit. As with other lawsuits seeking the revocation of administrative dispositions, litigation for the revocation of IPTAB decisions also goes through an examination of unlawfulness from both substantive and procedural perspectives. However, there is an issue as to whether the scope of examination in revocation suits against IPTAB decisions is limited to the grounds and evidence claimed in the IPTAB trial. There are two conflicting theories regarding this issue: the limitation theory and the nonlimitation theory.

For inter partes cases, the Supreme Court has upheld the nonlimitation theory on the following grounds: first, a revocation suit is classified as an appeals suit because it is filed against the IPTAB’s decision, which is an administrative disposition; therefore, the subject matter of the revocation suit is substantive or procedural unlawfulness in the decision; second, the litigant may argue and prove, in the process of the revocation suit, the reasons for the unlawfulness of the decision even if it did not rule on such reasons, and the court presiding the revocation suit may examine and judge on such reasons and take them as the basis for its decision unless there are special circumstances not to do so.⁵³

For ex parte cases, an administrative agency’s disposition limiting a party’s right without prior notice or an opportunity to submit opinion is unlawful and shall be revoked unless an exception applies, according to the Supreme Court.⁵⁴ The Supreme Court has taken the same position in patent rejection cases. In a suit seeking revocation of an IPTAB decision upholding a patent rejection, it held that the Commissioner of the KIPO may not raise a new ground of rejection that was not raised before the examiner or the IPTAB because the plaintiff was not given an opportunity to submit opinion disputing the new ground.⁵⁵ Nonetheless, this limitation is only applicable to the Commissioner of the KIPO (the defendant) and not to the patent applicant (the plaintiff). In light of the foregoing, the Supreme Court’s decision is generally viewed as having intended to protect the procedural rights of the applicant rather than having been based on the limitation theory.

Further, if the Commissioner of the KIPO claims new grounds in a revocation suit in line with the essence of the grounds for rejection and for which the applicant was given an opportunity to submit their opinion in the examination or IPTAB trial phase (and are thus just supplementary to the already notified grounds for rejection), such grounds may be admitted and serve as the basis for judging whether the IPTAB decision should be revoked.⁵⁶

8.4.2.6 Litigation procedures for revocation suits

8.4.2.6.1 Submission of a complaint

A revocation suit is initiated when the plaintiff submits a complaint to the competent court. The plaintiff must describe the following matters on its complaint in detail:⁵⁷

• the procedural background on the IPTAB trial;
• a summary of the administrative decision (the arguments of the parties and the decision thereon by the IPTAB at the trial stage);
• parts admitted and not admitted among the grounds for the decision;
• all arguments relating to the grounds for revoking the decision;
• a notice of related cases (e.g., pending IPTAB trial or lawsuit on the same patent); and
• the plaintiff’s opinion on the overall litigation proceedings, including any plan to request evidence.

Additionally, the plaintiff must be careful not to overlook the following basic evidentiary documents and requisite attachments, along with a power of attorney for litigation, a corporate register or a certificate of corporate nationality (if the party is a foreign corporation), and a certificate of service of the administrative decision:⁵⁸

• for a revocation case on rejection – the IPTAB decision, patent application, examiner’s preliminary rejection, amendment, opinion and final rejection;
• for a revocation case on invalidation – the IPTAB decision, original register, publication of registration and evidence relating to prior art; and
• for a revocation case on the scope of rights – the IPTAB decision, original register, publication of registration, explanatory documents and the drawings of the invention for review in the scope of rights confirmation action.

Once a revocation suit is lodged (upon submission of a complaint), the IPTAB decision subject to the revocation is prevented from being treated as final and conclusive. For this, the Patent Court requires that the purpose of a revocation suit, or an appeal against the revocation suit, be notified to the President of the IPTAB without delay.⁵⁹

8.4.2.6.2 Submission of answer

No later than three weeks from the service of the plaintiff’s complaint or brief containing the specific cause of action, the defendant must submit an answer, including the following matters, together with evidence cited in the answer and explanatory documents for evidence:

• an answer to the plaintiff’s demand;
• the parts admitted and not admitted among the plaintiff’s arguments;
• detailed rebuttal arguments on the parts not admitted among the plaintiff’s arguments;
• other arguments relating to the grounds necessary to maintain the decision;
• a notice of related cases;
• acceptance or denial of evidentiary documents submitted by the plaintiff; and
• the defendant’s opinion on the overall litigation proceedings, including a plan to request evidence.

8.4.2.6.3 Preparatory hearing

As in a civil patent suit, once key issues of a revocation suit are specified through the presentation of written arguments between the parties, a hearing date is immediately designated, and sometimes a date for a preparatory hearing as well. Preparatory hearings are usually conducted via conference call and supervised by a presiding judge serving as a commissioned judge. The following matters are generally discussed in the course of a preparatory hearing:⁶⁰

• the dates and number of trials and the matters to be addressed in each;
• deadlines for the submission of arguments and evidence (including deadlines for the submission of comprehensive briefs and an affidavit of an expert witness, and the number of submissions and length of briefs);
• whether to request evidentiary methods requiring a substantial amount of time, such as verification, appraisal and expert witness, and the deadlines for such requests;
• whether to designate a technical advisor;
• whether to hold a technical explanatory session by the parties;
• whether to first hold a hearing for claim construction;
• how to proceed the trial if a trial for correction or petition for correction is pending;
• whether to hold a parallel hearing if relevant cases, such as invalidation, confirmation of the scope of rights and infringement, are pending; and
• confirmation and summary of disputed issues.

8.4.2.6.4 Internal technical explanatory session

Once a date for the hearing is determined in a revocation suit, an internal technical explanatory session is held before the hearing date to increase the court’s understanding of technical issues. During the session, a technical examiner explains the background of relevant technology, along with other technical issues relating to the invention at issue and prior arts. Unlike civil patent cases, where internal technical explanatory sessions may be omitted because there are no technical issues, an internal technical explanatory session is held in almost all revocation suits.

8.4.2.6.5 Hearing

As in civil patent suits, during a hearing of a revocation suit, the examination of evidence, documentary evidence and so on are conducted in connection with the arguments of both parties, along with the identification and sharing of key issues, presentation of oral arguments regarding the key issues, and filing of applications by both parties for further evidence. Revocation suits often involve professional knowledge and complex issues relating to patents, so it usually takes a significant amount of time for parties to prepare their arguments. Accordingly, revocation suits are given sufficiently more time than for civil suits in general. For a civil patent case of first instance, hearings are conducted on multiple occasions, with an interval of about one month, before closing arguments. For a revocation suit, the court usually closes arguments after the first round of intensive or concentrated examination of each issue. This is because revocation suits rarely involve a dispute over relevant facts and instead focus only on the judgment of technical issues such as inventive step. Moreover, in most cases, the first hearing is often arranged as a technical explanatory session. Arguments in a revocation suit may also be presented in a foreign language so long as both parties consent and the court permits.

8.4.2.6.6 Relationship between invalidity and infringement proceedings

The Civil Procedure Act also applies mutatis mutandis to revocation suits (administrative patent lawsuits), except as otherwise provided for in the Patent Act and the Administrative Litigation Act.⁶¹ Therefore, revocation suits and civil patent suits have almost the same litigation and evidence collection procedures. Moreover, patent infringement suits and revocation suits are also very similar in terms of the key issues, considering that the grounds for invalidation of a patent may also be contended in a patent infringement suit. The difference is that a patent infringement suit deals with various issues concurrently, including whether the product of the other party falls within the scope of protection of the patent at issue, whether there are grounds for invalidation of the patent, and the assessment of damages. In a revocation suit, by contrast, only some of those key issues are contested, and such suits thereby progress more quickly.⁶²

8.4.2.7 Examination in parallel with an infringement suit

Related cases with the same registration number of IP rights are, in principle, allocated to the same judicial panel. If the parties to a case are the same, and the same or similar IP rights are assigned to different judicial panels, they may be allocated to the same judicial panel through a reallocation procedure. The parties must notify the judicial panels of such circumstances if related cases are allocated to or pending before different judicial panels.⁶³

When an infringement case and a revocation case of IPTAB decision involving the same patent right are pending concurrently before the same judicial panel and are litigated by the same parties – and when the need for a parallel hearing is recognized – the court will, in principle, hold the trial on both cases in parallel.⁶⁴

8.4.2.8 Evidence collection procedures

In revocation suits, the types of evidence and the process of requesting for evidence and conducting evidence examination are similar to those in civil litigation.⁶⁵ The difference is that, in a revocation case, the court may examine evidence ex officio if necessary.⁶⁶ However, this does not mean that the “doctrine of ex officio detection of facts” is adopted for the court to collect evidence on an ex officio basis. The principle of pleadings remains the governing rule, and the “doctrine of ex officio examination of facts” is adopted to allow the court to examine evidence and acknowledge facts by its own authority to the extent that its examination is supplementary and performed on the evidence available on record.⁶⁷

8.4.2.9 Appeal

The Patent Court’s decision in a revocation case may be appealed to the Supreme Court.⁶⁸ The appeal procedure in revocation cases is the same as that of civil cases, as discussed in Section 8.5.⁶⁹

8.4.2.10 Effect of a decision revoking an Intellectual Property Trial and Appeal Board decision

Once a court decision revoking an IPTAB decision becomes final and conclusive, the revoked decision becomes void without having the need for any action to be taken by the IPTAB. Additionally, administrative judges of the IPTAB must review the case and render another decision.⁷⁰ The grounds on which revocation was rendered are binding upon the IPTAB with respect to the case.⁷¹ For example, if a patent application of the plaintiff (the applicant) was rejected, followed by the IPTAB’s ruling to dismiss the application, and subsequently the Patent Court’s decision revoking the IPTAB’s ruling became final and conclusive in a revocation suit, the patent will be registered by the following process:

1. 1. The patent application is submitted.
2. 2. An examiner rejects the patent application.
3. 3. The IPTAB dismisses the applicant’s appeal.
4. 4. The Patent Court revokes the IPTAB’s decision.
5. 5. The decision is appealed to the Supreme Court, which affirms the appellate court’s (the Patent Court’s) revocation.
6. 6. The IPTAB revokes the rejection of the patent application, granting the appeal pursuant to the binding force of the judicial decision.
7. 7. The examiner grants the patent.