We combine technical insight with decades of prosecution experience to help secure effective patent protection in Japan.
ITOH & EBI is a Tokyo-based patent firm assisting clients with the acquisition, maintenance, and use of intellectual property rights in Japan.
The firm’s international practice is rooted in founder Shigeru Itoh’s work on Japanese patent matters for overseas companies, dating back to 1972.
Our patent work is centered on mechanical technologies—including mechanical components, machine tools, measurement and control systems, and production equipment—and also covers electrical, chemical, and materials technologies.
Each matter is led by the firm’s principal, who reviews the client’s instructions and objectives, the relevant technology, and the scope of protection required for the business. We then provide practical recommendations tailored to prosecution before the Japan Patent Office (JPO).
From translation and filing preparation through responses to Office Actions, we propose amendments, arguments, and other specific courses of action with due regard to claim scope and the strength and validity of the resulting patents.
By the Numbers
Since the firm’s founding in 2003
23
years
Patent applications handled
1,751
Filed for overseas applicants
983
56
% of all applications handled
Source: ITOH & EBI analysis of published Japanese patent applications handled by the firm, including its predecessor ITOH & ASSOCIATES, filed from January 2003 through April 2026; data current as of July 10, 2026. Overseas applicants are identified by the applicant of record.
HOW WE WORK
A Proactive, Practical Approach
to Prosecution in Japan
01 Specific Recommendations in Our Initial Report
When the JPO issues an Office Action, we analyze the differences between the claimed invention and the cited references. Our initial report includes an English translation of the Office Action, proposed amendments, draft arguments, an explanation of the likely effect of each option on claim scope, and our recommended course of action.
02 Issues Identified During Translation
We prepare faithful Japanese translations using terminology appropriate for Japanese patent practice. If we identify an issue that may affect examination or future enforcement, we explain the issue and recommend how to address it. Where appropriate, we propose a voluntary amendment for your approval.
03 Consistent Oversight by the Principal
From the initial instruction through document review, filing, prosecution, and registration, the firm’s principal maintains an ongoing understanding of the technology and prosecution strategy. For matters extending over several years, we work from the full record of prior correspondence and decisions.
SERVICES
Services for International Clients
Japanese Patent Filings and PCT National Phase Entry
We handle Japanese filings under the Paris Convention and PCT national phase entries in Japan, including review of filing documents, Japanese translation, filing, requests for examination, and registration procedures.
Responses to JPO Office Actions
We review the reasons for rejection and the cited references, and prepare amendments and arguments with our recommended course of action.
Patent Translation
We prepare Japanese translations of patent specifications, claims, and abstracts that accurately reflect the source text and use terminology consistently throughout. Where we identify an issue that may affect prosecution in Japan, we flag it separately from the translation and explain the reason and our proposed response.
Searches and Opinions
We conduct prior art, freedom-to-operate, and invalidity searches and provide opinions on patentability and infringement.
Design and Trademark Prosecution
We assist with filing, prosecution, and registration of designs and trademarks in Japan.
Annuities and Portfolio Management
We manage post-grant annuity deadlines and payments and assist with status monitoring and other maintenance matters for intellectual property rights in Japan.
PROFESSIONALS
Patent Attorneys
Principal / Japanese Patent Attorney
Qualified to act as counsel in specified IP infringement litigation, jointly with an attorney-at-law
YUSUKE EBI
Registration No. 17598 (registered in 2011)
Yusuke Ebi holds a degree in mechanical engineering from Tohoku University, where he specialized in robotics. In 2001, he joined Yamatake Corporation (now Azbil Corporation), where he worked in R&D on production equipment, semiconductor sensor packaging equipment, gas sensors, and laser-based sensors. He also gained first-hand experience as a named inventor on patent applications.
He joined the firm’s predecessor, ITOH & ASSOCIATES, in 2010 and registered as a Japanese patent attorney in 2011. Since then, he has advised Japanese and overseas companies on patent filing and prosecution, searches and opinions, and infringement-related matters, primarily in the mechanical field. He has led the firm as principal since 2018.
Selected Experience
- Patent prosecution involving mechanical components, machine tools, production equipment, sensors, and measurement technologies
- Japanese patent prosecution and coordination of overseas patent prosecution for Japanese and international clients
- Prior art searches, opinions, and infringement-related matters
- Invention seminars for corporate engineers
- Intellectual property lectures for university science and engineering students
Founder / Of Counsel
Japanese Patent Attorney
SHIGERU ITOH
First registered in 1978 (former Registration No. 8389); re-registered in 2026
Shigeru Itoh joined Yuasa and Hara in 1972, where he handled Japanese patent filing and prosecution for overseas companies. After registering as a Japanese patent attorney in 1978, he also handled numerous JPO trial and appeal proceedings and patent litigation matters. He became a partner at Yuasa and Hara in 1988.
In 2003, he established ITOH & ASSOCIATES, the predecessor of ITOH & EBI. Drawing on decades of experience in Japanese patent matters for overseas companies, he has served as Of Counsel to the firm since 2026.
Selected Experience
- Japanese patent filing and prosecution for overseas companies
- JPO trials and appeals, and patent litigation
- Patent prosecution primarily in the mechanical field
Our History
1972
Shigeru Itoh joined Yuasa and Hara and began handling Japanese patent matters for overseas companies.
1978
Shigeru Itoh registered as a Japanese patent attorney (Registration No. 8389).
1988
Shigeru Itoh became a partner at Yuasa and Hara.
2003
Shigeru Itoh established ITOH & ASSOCIATES, the predecessor of ITOH & EBI.
2010
Yusuke Ebi joined the firm.
2011
Yusuke Ebi registered as a Japanese patent attorney.
2018
The firm was renamed ITOH & EBI, and Yusuke Ebi became its principal.
2026
Shigeru Itoh became Of Counsel to the firm.
OFFICE & LOCATION
Office Information
| Firm | ITOH & EBI |
|---|---|
| Address | 4F DSG Hamamatsucho Bldg., 1-11-7 Hamamatsucho, Minato-ku, Tokyo 105-0013, Japan |
| Established | 2003 (as ITOH & ASSOCIATES; renamed ITOH & EBI in 2018) |
| info@itohpat.com | |
| Office Hours | Weekdays, 10:00–17:00 JST (UTC+9) |
| Languages | Japanese and English |
4F DSG Hamamatsucho Bldg., 1-11-7 Hamamatsucho,
Minato-ku, Tokyo 105-0013, Japan
- 5-minute walk from Hamamatsucho Station (JR Yamanote and Keihin-Tohoku Lines)
- 4-minute walk from Daimon Station (Toei Asakusa and Oedo Lines)
- 9-minute walk from Onarimon Station (Toei Mita Line)
- 9-minute walk from Shiodome Station (Toei Oedo Line)
Conflict Checks and Confidentiality
Before accepting a new matter, we conduct a conflict check. In your initial inquiry, please provide the names of the applicant, the instructing client, and other relevant parties, together with the type of matter and any applicable deadline. We treat information received in connection with inquiries and client matters as confidential, in accordance with our professional obligations and privacy policy.