Resolution of Intellectual Property Disputes

As high-quality and quantitative intellectual property experts,
we resolve intellectual property disputes.

Managing Partner, Mr. Kobayashi and Partner Mr. Yugeta have experienced many cases and have accumulated vast know-how. For example, Mr. Kobayashi passed the patent attorney examination in November 1978 and worked as a patent attorney at a patent firm. After passing the bar examination, Mr. Kobayashi has consistently handled intellectual property disputes.

After passing the bar examination in 1997, Mr. Yugeta worked with Mr. Kobayashi at Tamiya & Tsutsumi on various kinds of civil and commercial cases. Since then, he has overseen intellectual property disputes at Toranomon Sogo Law Office, and Yuasa and Hara from March 2004.

In patent litigations, it is very important to determine who the attorney will be. The number of patent litigations and other intellectual property disputes has seen a slight increase in recent years. However, both infringement lawsuits and revocation lawsuits have been shortened in the trial period.

In principle, a lawsuit seeking revocation of a trademark decision shall be closed by the first court hearing date. For this kind of expeditious IP dispute, if you do not ask a lawyer with a lot of experience and who understands the latest trends, the trial will be closed within a short time, and you will not be able to submit sufficient arguments and evidence.

Resolution of Patent Infringement Disputes


Patent infringement disputes are extremely specialized, as the Intellectual Property Division was established in the Tokyo District Court and the Intellectual Property High Court was established.
We have much experience in patent infringement lawsuits, and have gained extensive knowledge as a result of our continuous daily studies.

Practices in patent infringement lawsuits are divided between plaintiffs and defendants, including the know-how possessed by Kobayashi & Yugeta Law Office. However, it is difficult to define all of them, and since no two cases are ever the same, it is necessary to examine and make decisions on a case-by-case basis. Please feel free to consult with us at any time.




Plaintiffs' Practices

  • ①Acquisition of clues and infringing products
  • ②In-house preparations
  • ③Consultations with legal counsel
  • ④Sending warning letters
  • ⑤Preparation after warning
  • ⑥Preparation for filing action
  • ⑦Court filing and proceedings in the first Instance

Defendant’s Practices

  • ①Receiving a warning letter
  • ②Confirmation of the claim
  • ③Response after receipt of warning
  • ④Response to warning letter
  • ⑤Subsequent measures
  • ⑥Service of complaint and filing of answer

Design Act

The Design Act, along with Article 2, paragraph 1, item 3 of the Unfair Competition Prevention Act, protects industrial designs, subject to registration with the Japan Patent Office. However, the design of products can be protected for 20 years from the registration.

Claims in lawsuits and warnings must be made by argument, using the appropriate language; in accordance with the Design Act, a unique way of expressing design forms is used to depict them in language, and lawyers dealing with design claims require a high degree of expertise in this regard.

The number of disputes concerning the Design Act is very small compared to other intellectual property disputes, including those under the Patent Act. However, we have all experienced dealing with disputes concerning the Design Act.


Trademark Act

The Trademark Act, along with the Unfair Competition Prevention Act, protects corporate brands. Recently, the scope of application has been expanding, as exemplified by the fact that colors and sounds can now be registered independently.

Unlike other fields, the purview of the Trademark Act contains a lot of sensory factors, such as whether a trademark is classified as a class or whether the same character as a registered trademark is used as a "use" under the Trademark Act. Without an analysis of a large number of judicial precedents and trial decisions, it is very difficult to predict the case in question.

The Trademark Act would be problematic in business during the phase of the maintenance of rights as follows:

  • ①Application for a new trademark.
  • ②Registered trademarks are claimed to be invalid or revoked by other companies; or desire to make invalid any registered trademarks that interfere with other companies.

In disputes, a typical situation is as follows:

  • ③Third parties are infringing our trademark rights, so we want them to stop selling their products for the purpose of protecting our brand, or the owner of the trademark rights claims to have stopped selling our products on the ground of infringement of the trademark rights.

Of these, patent attorneys who handle applications are more specialized than attorneys-at-law for ① above.
However, in cases ② and ③ since the final tribunal is the court, it is advisable to use a lawyer who has had the same training as a judge, and who has the same unique way of think as the judge, such as the fact-finding of requirements and facts, and who is proficient in trademark law, in order to develop the argument and predict the outcome of the lawsuit.

In particular, with regard to case ③, unless an appropriate forecast is made from the dispatch and receipt of a warning letter, which represents the initial stages of the dispute, a warning may be sued under Article 2, paragraph 1, item 15 of the Unfair Competition Prevention Law against the warning party.

Our firm specializes in intellectual property law; and Mr. Kobayashi in particular, has a lot of experience in numerous trademark infringement lawsuits, litigations seeking revocation of trial decisions, and patent office invalidations and non-use revocation trials.


His knowledge and experience have been acknowledged and highly praised, for example, "The Japan Trademark Association makes annual requests for lectures from him to people in charge of intellectual property at companies," "The Japan Patent Attorneys Association requests lectures from him to be given to patent attorneys who are experts in intellectual property rights," and "he has also been asked to accept lawsuits in the middle of lawsuits at the request of other lawyers."

Copyright Act

The Copyright Act protects creative expressions, and copyrights occurring in most of the Content Businesses, such as novels, music, paintings, and films.

Unlike other intellectual property laws such as the Patent Law and the Trademark Law, the Copyright law is characterized by the creation of a work without any official procedures such as registration with the Japan Patent Office.

As a result, copyrights can occur in everything, including inter-company documents, material appearing on the Internet, and small illustrations. Copyright infringement is always a risk in business, due to the constant copying and pasting of documents, copying of electronic files, and creation of PDF documents. In order to avoid being accused of infringing copyrights, it is essential that you are in close contact with lawyers who are knowledgeable about copyright law.

Mr. Kobayashi teaches at a law school, and we have sufficient knowledge of the Copyright Law, and promptly respond to requests for daily copyright counseling from many of our corporate clients.


We have a system in place to enable us to respond promptly to any issues that may arise in daily copyright usage. If we want to avoid risks without sacrificing the speed of our business, we hope that you will be able to take advantage of a retainer agreement with our lawyers.

Unfair Competition Prevention Act

The Unfair Competition Prevention Law ("Unfair Competition Law") classifies competitive methods (unfair competition) that are regarded as unfair in competition between enterprises, and allows victims of unfair competition to demand injunctions against unfair competition and compensation for damages incurred.

Non-Competition Law includes a wide range of issues, including trade secrets, which have become a hot topic recently. However, a significant portion of these cases are those under Article 2, paragraph 1, items 1 to 3.

Article 2, paragraph 1, item 1 and Article 2, paragraph 1, item 2 of the Non-Competition Law prohibit the use by other companies of similar logos and designs of famous products, and more than half of the cases of Non-Competition Lawsuits fall under this category. Unlike the Trademark Law, it is not necessary to register such logos and designs etc. with the Japan Patent Office on the condition that they are famous. This type of law is often used in conjunction with the Trademark Law to protect a company's brand image. In particular, for a well-known company engaged in the B to C business, it is highly valued as a basis for the company's desire to cease any action that could damage its brand image.

However, the hurdles that are recognized as famous in the courts are high, and at the warning stage, it is often argued that the warnings are similar even if they are not necessarily similar. Therefore, it is important to carefully analyze the case when a warning is received.

Article 2, paragraph 1, item 3 of the Non-Competition Law is a law for measures against counterfeits. Without registration or other means, counterfeits can be eliminated for three years from the date on which the new product was first sold, and the design of the new product can be protected with labor and expense. Since the protection period is short (three years), we need to consider the option of a provisional disposition at a low cost of \2,000 for stamps paid to the courts because the trial period is short (although the money is returned, we need to deposit a separate security deposit).

In such cases, the deadline is very short, and it is not unusual to have an upcoming deadline when you find a lawyer who is familiar with anti-competitive practices. Anyone who receives aggressive warnings from a large company and who has never experienced an intellectual property lawsuit before would be quite anxious.

Kobayashi & Yugeta Law Office deals with these kinds of cases on a regular basis, and with advice backed by experience we can provide the right path towards a resolution. Please contact us if you receive a warning letter.