About Us

About Us

Welcome message

Thanks to everyone’s support since our founding in April 1974, we have been able to continue to grow and to provide a wider assortment of services to our valued clients, to whom we owe a debt of gratitude.
We have enhanced our strengths by building a team of highly experienced patent attorneys and engineers with knowledge in a wide range of technical fields, many of whom have considerable corporate and industry experience, were past patent examiners at the JPO, and have bilingual talent.
Our team has obtained over 30,300 patents in Japan and 24,000 patents abroad covering technical fields such as computers, software, communications, electronics, mechanical technologies, medical devices, pharmaceuticals, and gaming. This deep hands-on experience is the core of our expertise and enables us to provide the highest quality prosecution services. It is also why we have been so effective in litigation projects, particularly in Japan where there is no jury system.
From patent litigation cases involving SEPs related to telecommunications and pharmaceuticals, to extensive patent prosecution experience, we have a tried and tested history of success as an all-round player in the dynamic world of IP.
Furthermore, we recognize that designs and trademarks are also essential for maximizing product value and increasing market share in increasingly competitive markets. At Ohtsuka Patent Office, we work hard to support our clients in the creation and enforcement of design and trademark rights.
The growth of our firm is testament to our ambition and dedication to our clients in realizing their goals as technology continues to evolve. We will continually keep ahead with the complex world of new technologies to provide an excellent and timely service to our clients.

Yasuhiro Ohtsuka, Managing Partner

Yasuhiro Ohtsuka
Managing Partner

Main services

Prosecution of Japanese and foreign patents (spec / claim drafting) and maintenance thereof

Patent portfolio management and strategic consulting

IP litigation and Japanese/foreign litigation support

Opinion work

Patent searches and freedom to operate (FTO) studies

Patent licensing and contracts

Trademark / design clearance search and consulting

Contact Information/Map

Name Ohtsuka Patent Office, P.C.
Established in April 1974
Chairman Yasunori Ohtsuka
Managing Partner Yasuhiro Ohtsuka
Google Map
Telephone +81-3-5276-3241
Contact us
  • Tokyo Office: You can find us in Kojimachi, in central Tokyo.