An International Guide to
Patent Case Management for Judges

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8.6.7 Evidence

In general, the Civil Procedure Act does not provide pre-trial discovery processes like depositions and interrogatories in the United States. Instead, evidence is produced during trials. In exceptional cases where certain evidence may not be available during the trial unless it is timely preserved, a party may request a court order to examine evidence prior to filing the lawsuit. All requests for evidence production are made by petition to the court, and the court will exercise its discretion in granting or dismissing the petition, balancing the need for the evidence and any delay or harm that may be caused by the production of the evidence. Any party that submits documentary evidence or files requests for witnesses, inquiry of facts, entrustment to send a certified and authenticated copy, order to submit documents, inspection, appraisal and so on must specify, in detail, the matters to be substantiated by the evidence. Documentary evidence

Documentary evidence submitted in civil patent cases includes patent specifications, general books (technical literature), published materials, patent gazettes or laid-open gazettes, and patent registers. Any product, model, photograph, video or other material capturing or using the patent can also be submitted as evidence to help in the understanding of technical aspects of the patent. In principle, documentary evidence must be submitted in its original copy. However, in practice, it is acceptable to submit a scanned version of the original copy unless the other party disputes the existence or authenticity of the original copy, in which case the nonconverted original copy must be made available for examination on the trial date. Any document written in a foreign language must be submitted along with a translated version,118 the exception being for documents written in the permitted language in an international case.119 Inspection

Either party may ask the court to inspect samples of the other party’s products (e.g., the accused’s infringing articles) or conduct an on-site inspection of the other party’s property (e.g., the defendant’s manufacturing facility). The petitioner may also request that the court order the other party or a third party to submit the product to be inspected, if the petitioner does not already have a sample of the product in its possession. Upon submission, the court may choose to inspect it directly or may appoint an expert to inspect the product and submit an opinion based on relevant findings.

A party seeking an on-site inspection must persuade the court that the inspection is necessary. For example, an on-site inspection of the defendant’s premise may be necessary to prove infringement in a case involving a manufacturing process. If a petition for an on-site inspection is granted in such a manufacturing process case, the court will usually appoint an expert witness to accompany the judges to help perform the inspection and identify the relevant manufacturing process. Court-appointed expert evaluation

The court can also appoint independent experts to provide testimony on complex technical issues that require input from experts (Article 335 of the Civil Procedure Act). The court may appoint an expert at the request of one of the parties or at its own discretion. Further, the court may ask public institutions, schools, organizations that have appropriate facilities, or foreign public institutions to provide their expert opinion (Article 341 of the Civil Procedure Act).

The court may appoint one or more experts to conduct testing or to submit an opinion on disputed issues that require special knowledge or experimentation, usually upon petition by one of the parties. In rare cases, the court may appoint one or more experts at its discretion. A party may petition the court to seek the opinion of a specific expert, in which case the other party may object to the recommended expert by presenting evidence of bias or other disqualifying grounds. The court has broad discretion regarding the selection of its own expert or in denying a petition for an expert.

Each party may petition to disqualify a potential expert by indicating that the person is incapable of providing a fair and true opinion (e.g., the expert was granted research funds by a party or its affiliates) or that they are not properly qualified. The Civil Procedure Act does not limit court-appointed experts based on their nationality or residence; the sole requirement is that the person has the necessary knowledge and experience to provide the expert opinion.

Court-appointed experts, like witnesses, are required to take an oath before the court that they will provide their opinion based upon what they believe to be true and correct and be subject to criminal punishment for perjury. Further, if necessary, a court-appointed expert may enter a party’s premise with the court’s approval. This is an exercise of the court’s power by the court-appointed expert. Orders promoting evidence production

In civil cases, a party seeking to file documentary evidence possessed by the opposing party or a third party may request that the court order the holder of the document to submit the document (a “document submission order”).120 If the respondent does not comply with an order under the Civil Procedure Act, the court may find what is alleged by the petitioner as to the contents of the document to be true.

Taking into account the distinct nature of patent cases, where evidence is often concentrated in the other party’s possession, the Patent Act expands the scope from documents specifically to materials more broadly and has enhanced the disadvantage to the noncompliant party (a “material submission order”). Failure to comply with a material submission order may result in the court admitting not only the petitioner’s contention about what is in the material but also the contention about the fact sought to be established by the materials as valid under certain conditions. The following sections discuss the document submission order under the Civil Procedure Act and the material submission order under the Patent Act. Document submission order

Under Article 343 of the Civil Procedure Act, a party may petition the court to order the other party or a third party to submit a document known to be relevant to the merits of the case. Under Article 345 of the Act, a petition requesting the court to order document submission must clearly indicate the document title, its purpose, the person holding the document, the facts the document proves and the basis for the obligation to produce the document. The holder of the document has the obligation to produce the document under Article 344 if (i) they are a party and have referred to the document in the lawsuit, (ii) the petitioner is legally entitled to demand delivery or perusal of the document from the holder, or (iii) the document has been made for the benefit of the petitioner or concerns the legal relationship between the petitioner and the document holder, with some exceptions as prescribed in the provision.

Beginning July 9, 2019, accused patent or utility model infringers must also respond to credible infringement claims with evidence rather than with simple denials (which have been common where the evidence of infringement is entirely within the defendant’s premises and therefore difficult for the plaintiff to obtain through court orders). If a prima facie showing of likely infringement is made, an accused infringer denying infringement must present evidence of the actual process or product it is practicing or else risk the court presuming that the accused infringing activity has actually taken place. Material submission order

The Patent Act has been amended (partial amendment by Law No. 14112, effective June 30, 2016) to expand the scope of submission orders from “documents” to “materials,” which may also include electronic files, video clips or any other nondocumentary form of data. The Act was amended to also prevent parties from refusing to comply on the basis that the materials contain trade secrets. Under the amended law, the petitioning party should first establish, via an in camera proceeding if necessary, that the materials actually contain trade secrets. Even if successful, the material holder cannot simply refuse to comply with the order if such evidence is deemed necessary to prove infringement. Instead, the holder may request that the court limit the scope of disclosure or the persons who can access the materials.

If a requested material is withheld without justification, the amended law permits the court to presume that the other party’s claim based on the facts sought to be proved through the material is true. These changes were designed to make it easier for patent litigants in the Republic of Korea to obtain the necessary evidence regarding infringement and damages. The amendment applies to all infringement actions filed on or after June 30, 2016. The court preserves broad discretion in granting requests for submission orders. Evidence preservation (before or during an infringement action)

Evidence preservation is a tool used to obtain evidence that is otherwise difficult to secure. Petitions to preserve evidence have been granted in some patent infringement cases. To be successful, the petitioner should establish that there is a likelihood or reasonable probability of patent infringement and establish the necessity for evidence preservation. If successful, the court will issue a ruling that states to the effect of “(1) evidence examination shall be conducted with regards to this case and (2) the respondent is hereby ordered to submit materials.” In the annex to the ruling, the subject,121 the place122 and date of examination will be specified for evidence examination, as well as the facts to be proven and the subject materials123 for material submission.124

A petition for evidence preservation can be filed either before or during an infringement action. Before filing an infringement action, the petition for evidence preservation should be submitted to the district court having jurisdiction over the place of residence of the party possessing the alleged evidence or the location of the evidence intended for inspection, and the case will be heard by a single judge. After filing a lawsuit, the petition can be submitted to the court where the lawsuit has been filed, and the case will usually be heard by the same panel reviewing the lawsuit. Experts Witnesses (including expert witnesses)

Although documentary evidence is the most frequently used form of corroboration in civil patent litigation, the use of witness examination to prove factual background has been gradually increasing. It is particularly common in civil patent cases to conduct expert witness examinations of people who are acknowledged to have expertise in the particular technology. Expert witness examination is different from other witness examination in that the latter focuses on the facts that the witness has actually experienced in person, whereas an expert witness in a patent case is mostly called upon to testify on matters such as (i) the technical level of a person having ordinary skill in the art at the time of filing of the patent, (ii) the disclosure of the prior art, (iii) analysis and comparison of the infringing goods, (iv) the amount of loss caused by the infringement and (v) the reasonable amount of royalty, among others. To call an expert witness to the stand, the petitioner must submit a “Basic Statement for Expert Witness” to the court. This form is available in the practice directions of the Patent Court and the IP divisions of the Seoul Central District Court.125

The Civil Procedure Act prescribes several ways that experts may provide their opinions to the court. Expert testimony may be submitted either through a declaration or through direct testimony before the court. Declarations are the more commonly used method. Either party to the litigation may introduce independent expert declarations as evidence in support of its case, and such declarations may be based on the expert’s own testing and knowledge or on other evidence reviewed by the expert.

Expert witnesses may also be called to testify at the trial, usually upon a request by a party. The questions to be asked must be submitted to the court in writing prior to the trial. Direct examination usually requires only a very brief answer. Whether to allow expert testimony is at the court’s discretion, and, if it is allowed, the other party will have the opportunity to cross-examine the witness. Questions for cross-examination and redirect examination need not be presented to the court in advance. The court may also appoint experts to evaluate the disputed technologies or damages-related facts.126 Technical expert support Judicial technical examiners

The Patent Court has judicial technical examiners providing full-time expeditious and effective support in dispute resolution through the specialized examination of issues surrounding technical matters in patent or utility model cases.127 The judicial technical examiners in the Patent Court have expert knowledge and experience in scientific and technical fields, such as machinery, communications, electrics and electronics, chemistry, drugs, agriculture, and construction. They come from a variety of backgrounds: for example, KIPO examiners, patent attorneys and researchers in the relevant fields, often with Master of Science or PhD degrees. The KIPO also dispatches its division heads to the Patent Court as judicial technical examiners.

Upon the request of the judicial panel, judicial technical examiners provide opinions on technical matters in suits involving patents and utility models and, if deemed necessary by the panel, participate in preparatory hearings and trials and ask questions to the parties with the permission of the presiding judge.128 In principle, each patent case of the Patent Court has a judicial technical examiner having expertise in the field assigned to the case, and the judicial panel holds a technical explanatory session before the trial, during which the judicial technical examiner helps the judges to understand the technical issues of the case.129 The IP divisions of the Seoul Central District Court, in charge of most of the first-instance patent cases, and the Supreme Court, in charge of the final trials of all patent cases, have judicial technical examiners as well. Technical advisors

In addition to judicial technical examiners, the court may choose to appoint a technical advisor to provide expert opinion on a particular issue of the case. Technical advisors are selected from a pool of registered experts in a wide variety of technical fields, including machinery, communications, electrics and electronics, chemistry, drugs, agriculture, and construction. Most of them are researchers of national research institutes or professors teaching in graduate schools.

Technical advisors participate in the litigation by either submitting written opinions or attending on the trial date to provide explanations or opinions on technical matters and, with the permission of the presiding judge, to ask questions to the parties or witnesses. These experts are bound by confidentiality obligations in connection with the cases in which they participate and are deemed government employees for the purpose of the bribery provision under the Criminal Act.130

Technical advisors are distinguished from judicial technical examiners in that they are outside professionals appointed on a case-by-case basis, whereas judicial technical examiners work full-time at the court.