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Patent Litigation | Successful Recognition of a Petition for an Invalidation Trial by Pointing Out a Violation of the Patent Specification Requirements

This case study on patent litigation illustrates the importance of the specification description requirements.

A petition for an invalidation trial was filed (a request contesting an administrative action before an agency prior to court litigation, comparable to seeking administrative review) because the patent specification requirements were not satisfied, and the Supreme Court granted the petition.

CONTENTS
  • 1. Patent Litigation, Whether the Patent Specification Requirements Were Violated as the Issue
  • 2. Patent Litigation, the Lower Court's Determination
  • 3. Patent Litigation, the Supreme Court's Determination
  • 4. Patent Litigation, Daeryun's Strategy?

1. Patent Litigation, Whether the Patent Specification Requirements Were Violated as the Issue

In this case, which developed into patent litigation, the issue was whether the patent specification requirements had been violated.

The case, which developed into patent litigation, concerned the patented invention of a "compact telephoto lens assembly" required for the camera of a mobile device.

The patent was an invention of a product providing a compact telephoto lens assembly that has a ratio of the total track length to the effective focal length smaller than that of existing lens assemblies while still maintaining good image quality.

The technical feature of the invention in this case lies in the fact that, despite the short track length of the lens assembly, it functions as a telephoto lens while achieving good image quality.

The specification of the invention described, among other things, the efficacy and how, through examples of combinations of lens elements, it helps bring all fields of view into focus on the image plane and reduces chromatic aberration.

Company A registered a patent specification for the compact telephoto lens assembly in question. Company B, however, filed a petition for an invalidation trial of the registration of the patented invention on the ground of a violation of the patent specification requirements, asserting that a manufacturing method meeting the standards of the patent specification was not set forth, and the lower court rendered a decision granting that petition.

In response, Company A filed a final appeal seeking revocation of the trial decision on the invalidation petition.

2. Patent Litigation, the Lower Court's Determination

Article 42(3)1 of the Patent Act provides that an invention shall be described clearly and in detail so that it can be readily worked.

This is intended to disclose the content of the patent-applied invention so that a third party can readily understand it from the specification alone, thereby clarifying the technical content and scope sought to be protected.

The degree of description in the specification required under the above provision means a degree that allows the invention to be accurately understood and at the same time reproduced based on the described content alone. (See Supreme Court, Decision of November 24, 2006, 2003 Hu 2072)

Although working examples are not required, where a person ordinarily skilled in the art cannot produce or use the product based on the description in the specification alone, without adding excessive experimentation or special knowledge in light of the level of technology at the time of the application, the description requirements should be deemed not to have been satisfied. (See Supreme Court, Decision of September 24, 2015, 2013 Hu 525)

The specification in the above case did not describe how a lens assembly achieving good image quality could be produced within the scope of claims defined under the Patent Act.

There was no suggestion or hint from which a person ordinarily skilled in the art could infer that production was possible according to the manufacturing method described in the above specification, and there was also no material indicating that such a lens assembly could be produced with the level of technology at the time of the application for the corrected invention in this case.

In the end, a person ordinarily skilled in the art could not produce the product without adding excessive experimentation or special knowledge in light of the level of technology at the time of the application.

For the above reasons, the lower court in this patent litigation determined that the description of the invention was not stated clearly and in detail so that a person ordinarily skilled in the art could readily work the invention.

3. Patent Litigation, the Supreme Court's Determination

Dissatisfied with the lower court's judgment in the patent litigation, the plaintiff filed a final appeal seeking revocation of the trial decision.

Where, even in light of the common technical knowledge at the time of the application, the content disclosed in the description of the invention cannot be extended or generalized to the scope of the invention stated in the claims, the claims cannot be regarded as supported by the description of the invention. (See Supreme Court, Decision of May 11, 2006, 2004 Hu 1120)

The Supreme Court stated that, with respect to the technical description that is the core of the patent, it was reasonable to find that a person ordinarily skilled in the art could not produce the lens assembly from the content described above without adding excessive experimentation or special knowledge, and, accepting the lower court's reasoning, it dismissed the final appeal in this patent litigation.

4. Patent Litigation, Daeryun's Strategy?

To prepare for patent litigation, it is most important to draft the patent specification accurately and clearly.

For this reason, it is best to draft it from the patent specification stage with the assistance of an attorney experienced in patent law.

Through its 🔗Intellectual Property Rights Group, Daeryun Law Firm LLP responds to disputes with attorneys who have practical experience in matters relating to copyrights, patent rights, trademark rights, unfair competition, trade secrets, and related unlawful acts.

If you need professional legal assistance regarding patent rights, you are welcome to request a consultation with an attorney of the Daeryun Intellectual Property Rights Group.

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