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Nagato & Partners has been expanding with the addition of attorneys and technical professionals in various fields including electrical and electronic engineering, physics, materials, and chemistry as well as mechanical and mechatronic engineering. Nagato & Partners has about forty members in total including patent and trademark attorneys.

Kanji NAGATO Executive Director, Patent Attorney

Specialty Mechanics, Design

After finishing his master’s course in mechanical engineering at Kyoto University, engaged in research and development of aircraft jet engines at the Aeronautics and Space Division of IHI Corporation for about ten years, and established Nagato & Partners in 1985. The technical fields in which he has worked all these years include mechanical engineering, hydrodynamics, combustion engineering, heat transfer engineering, control engineering, production/processing engineering, and design and trademark. Kanji is a member of AIPPI, APPA, LES, VPP, IPO, Japan Patent Attorneys Association, Japan Trademark Association, Japan Intellectual Property Association, and is qualified as an arbitrator/mediator at Arbitration Center for Industrial Property. The membership in these organizations has supported his longtime success as a practitioner in the intellectual property field. He speaks Japanese and English.

Kanji Nagato

Shiro AIHARA President, Patent Attorney

Specialty Mechanics

Completed a Bachelor of Engineering (mechanical engineering) at Tohoku University. He has eight-year work experience with Nissan Motor Co., Ltd., where he engaged in vehicle manufacturing technology development. Because of his skills acquired at Nissan in the fields of welding, industrial robots, transport, etc., Shiro excels at mechanics, automobile engineering, and mechatronics. He is a member of Japan Patent Attorneys Association, and speaks Japanese and English.
Shiro Aihara

Kanji INOUE Partner, Patent Attorney, Foreign Client Relations

Specialty Electronics, Physics, Mechanics

Assumes the responsibilities in the development of new clients and the prompt respond to our client requests. After completing a Bachelor of Applied Physics at Tokyo University, he worked for Bridgestone, a global tire manufacturer, to engage in new tire plant design, tire production machine development, R&D of diversified products such as robots driven by pneumatic rubber actuators. At Bridgestone, he was also involved in worldwide marketing on a vast variety of products. Kanji gathered practical IP experience at both Bridgestone and patent firms. With this wide range of career and experience, he joined Nagato and Partners in 2010. He is a member of Japan Patent Attorneys Association, AIPPI and VPP (Vereinigung von Fachleuten des Gewerblichen Rechtsschutzes). Speaks Japanese, English, and German.

Nobuyuki OKAJIMA Partner, Patent Attorney

Specialty Mechanics, Chemistry

Completed a Bachelor of Agriculture (forest product major) at Tokyo University of Agriculture and Technology. In addition to the experience in a paper manufacturing company as an engineer, he engaged in Intellectual Property Division of Japan Tobacco, Inc., handling various cases related to tobacco manufacturing machines, material testing machines, vending machines, etc. He specializes in mechanics/mechatronics, electrical/electronics, chemistry, and material science, and is a member of Japan Patent Attorneys Association. His languages are Japanese and English.
Nobuyuki Okajima

Yasuhiko OSHIMOTO Partner, Patent Attorney

Specialty Trademark

He graduated from Keio University, Faculty of Technology, Administration of Engineering.
After about twenty years’ experience at a patent firm in Tokyo, he set up his own firm in 1997. He joined Nagato & Partners with running his firm.
He is a member of:
Japan Patent Attorneys Association (JPAA) (1983-present), where he was:
・Council member (1989-1990)
・Vice-chair of Trademark Committee (1991-1992, 1994-1995)
・Chairman of Trademark Committee (1997-1998)
The Asian Patent Attorneys Association (APAA)
Japan Trademark Association (JTA) (1988-present), where he was a Secretary-general in 2002-2013
In addition, he experienced:
Study Committee of International Classification of Japan Patent Office (1996-1997)
Committee member of Unfair Competition Prevention Act of METI (2003, 2005)

Yasuhiko Oshimoto

Norio HAGI Partner, Patent Attorney

Specialty Biotechnology, Chemistry

After finishing his master’s course in the industrial biochemistry of the faculty of engineering at Kyoto University, engaged in research and development of an artificial sweetener (aspartame) and clinical diagnostic kits using monoclonal antibodies at R&D Department of TOSOH Corporation for seventeen years. And he engaged in practices relating to intellectual properties and various contracts at IP department of TOSOH Corporation and the affiliated companies for seventeen years, bofore joining Nagato & Partners in Aug. 1st, 2013. His technical field is biochemistry, organic and inorganic chemistry. He is a member of Japan Patent Attorneys Association, and speaks Japanese and English.

Norio Hagi

Kenji TERAMACHI Patent Attorney

Specialty Mechanics

Graduated from Tokyo University, Engineering Faculty, Industrial Mechanical Engineering Department as a bachelor and then had engaged in development and design of gas turbine engines for power generation and jet engines at IHI Corporation for 17 years, before entering Japanese Patent Office (JPO). At JPO, he worked as an examiner in the mechanical fields including rotating machines such as turbines, engines. With his career for ten years at JPO, he joined Nagato & Partners in 2015. He is a member of Japan Patent Attorneys Association, Gas Turbine Society of Japan and VPP (Vereinigung von Fachleuten des Gewerblichen Rechtsschutzes). He speaks Japanese, English and German.

Mariko YOKOYAMA Patent Attorney

Specialty Physics, Electronics, Mechanics

After completing a Master of Applied Physics at Waseda University, she was involved in Si-device patterning process at Electronic Devices Group of Fujitsu Limited for three years. She had twenty-nine year experience with the IP firms in Tokyo and was engaged in domestic, inbound, and outbound cases of drafting and prosecution for patent related to semiconductor device, electronics, electric devices, office equipment, and power tool. She joined Nagato and Partners in 2019. She is a member of Japan Patent Attorneys Association. Her languages are Japanese and English.


Hajime NAKAMURA Patent Attorney

Specialty Mechanics, Control, Physics

After completing a Bachelor of Applied Mechanical Engineering at Chuo University, he worked in Bridgestone and Nissan Motor for about ten years before entering the IP firm in Tokyo. At Bridgestone, he had an experience of the development associated with the motorcycle tire as an engineer in addition to an experience as a technical support stuff to advise regarding to the tire for some racing teams. At Nissan Motor, he took charge of the development of some suspension parts (arms, links, stabilizers, bushes, wheels, tires and so on). At IP firm for about nine years, he was engaged in domestic, inbound and outbound work of drafting and prosecution for patent. He has handled a large number of inventions and provides expertise in technological fields such as transmission, clutch, brake, suspension, tire, bearing, oil seal, gasket, pump and so on. He joined Nagato and Partners in 2019. He is a member of Japan Patent Attorney Association, speaks Japanese and English.


Jacobus Sonderhoff

Specialty Applied physics, optics, machine vision, ceramic components, sensors, batteries

Following completion of his degree in physics (specialisations in astrophysics, digital image processing / machine vision) at King’s College London, Mr. Sonderhoff worked for Siemens in Munich first as an engineer (optical quality control of memory chips) and then as a patent engineer in the patent department, followed by his independent work for patent law firms and industry in Munich and Zurich. In 2009, he decided to pursue his career in Tokyo at the law and patent law firm Sonderhoff & Einsel as a technical advisor and a manager in the electrical engineering section, followed by his role as account manager in the marketing section. From 2016 to 2019 he worked at the Zurich-based law and patent law firm Rentsch Partner and deepened his experience in European patent practice and international business development. He joined us at Nagato & Partners in April 2021 in a business development role, and since passing the European qualifying examination, as a European Patent Attorney in an advisory capacity. He speaks English, German, Japanese and French fluently.

Jacobus Sonderhoff