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AIHARA & PARTNERS is steadily growing by adding patent attorneys and patent engineers to its team with a focus on electrical engineering, physics, materials science, chemistry, mechanical engineering and mechatronics. AIHARA & PARTNERS today consists of about 40 professionals including patent attorneys, patent engineers and administrative staff.

Shiro AIHARA President, Patent Attorney

Specialisations Mechanics, mechatronics, automotive incl. manufacturing, technologies, welding, vehicle control

Mr. Aihara completed his degree in mechanical engineering at Tohoku University. He began his career as an engineer at Nissan Motor Co., Ltd., where he worked for 8 years and developed various vehicle manufacturing technologies, in particular welding processes, industrial robotics and vehicle conveyor and vehicle production machines. In 1993, he joined Nagato International Patent Office, and in 2011, he became senior partner at Nagato & Partners. Since 2018, he is President of the firm. Mr. Aihara’s areas of expertise lie in mechanics, automotive engineering and mechatronics. He is a member of the Japan Patent Attorneys Association and speaks Japanese and English.
Shiro Aihara

Kanji INOUE Partner, Patent Attorney, Business velopment

Specialisations Electronics, physics, mechanics

Following completion of his degree in applied physics at the University of Tokyo, Mr. Inoue worked at Bridgestone where he designed and developed new tires along with machines for their production. He was also engaged in research and development of various products such as pneumatic actuators and thereby driven robots. Furthermore, Mr. Inoue was involved in the worldwide marketing of a wide palette of Bridgestone products. Mr. Inoue gained experience in intellectual property at the patent department of Bridgestone and then in private practice. With this extensive experience, he joined Nagato and Partners in 2010 and is now also engaged in foreign client relations. He is a member of Japan Patent Attorneys Association, AIPPI, VPP (Germany) and speaks Japanese, English, and German.

Yasuhiko OSHIMOTO Partner, Patent Attorney

Specialisations Trademark

Mr. Oshimoto studied industrial engineering at Keio University, Faculty of Technology, Administration of Engineering. Following completion of his degree, he worked at a patent law firm for 20 years, after which, in 1997, he founded his own law firm. In 2020, he entered a cooperation arrangement with Nagato & Partners and has since continued to run his firm in parallel. A member of the Japan Patent Attorney’s Association since 1983, Mr. Oshimoto was a Council member there from 1989 to 1990, Vice-chair of the Trademark Committee from 1991 to 1992 and from 1994 to 1995, and Chairman of the Trademark Committee from 1997 to 1998. Mr. Oshimoto is also a member of the APAA (Asian Patent Attorneys ssociation) and of the JTA (Japan Trademark Association), where he was Secretary General from 2002 to 2013. He was furthermore in the International Classification Study Committee of the JPO from 1996 to 1997 and also a Committee member of the Unfair Competition Prevention Act of the METI (Ministry of Economy, Trade and Industry) from 2003 to 2005. Mr. Oshimoto speaks Japanese and English.

Yasuhiko Oshimoto

Norio HAGI Partner, Patent Attorney

Specialisations Biotechnology, chemistry

Following completion of his degree in industrial biochemistry at the Faculty of Engineering at Kyoto University, Mr. Hagi worked in R&D at Tosoh Corporation for 17 years, particularly on the production of the artificial sweetener Aspartame and on testing methods based on monoclonal antibodies including their corresponding clinical diagnostic kits. Mr. Hagi then transferred to the patent department of the company before joining Nagato & Partners in 2013. Today, he focuses on patent prosecution in the fields of biochemistry and organic / inorganic chemistry. He is a member of the Japan Patent Attorneys Association and speaks Japanese and English.
Norio Hagi

Kenji TERAMACHI Patent Attorney

Specialisations Mechanics, combustion, rotation devices

A mechanical engineering graduate of the University of Tokyo, Mr. Teramachi worked in R&D at IHI Corporation for 17 years where he designed and developed jet engines and gas turbines for power generation. He then pursued his career as a patent examiner at the JPO (department for mechanical engineering, in particular turbines). With 10 years experience at the JPO, he joined Nagato & Partners in 2015. Mr. Teramachi is a member of the Japan Patent Attorney’s Association, the Gas Turbine Society and the VPP (Germany). In 2020, Mr. Teramachi completed his training as a qualified German - Japanese IP translator by passing the qualifying examination (Intellectual Property Translation Proficiency Examination). He speaks Japanese, German and English.


Mariko YOKOYAMA Patent Attorney

Specialisations Physics, electronics, mechanics

Following completion of her degree in physics at Waseda University, Ms. Yokoyama worked for 3 years at Fujitsu Corporation in the Electronic Devices Group, where she developed structuring processes for silicon components. She then began her career in intellectual property in private practice where she handled a large number of patent applications of foreign and domestic applicants in the fields of electrical engineering (particularly semiconductors), electronic office equipment, and electronic tools. She joined Nagato & Partners in 2019. Mr. Yokoyama is a member of the Japan Patent Attorneys Association and speaks Japanese and English.

Masayuki TORATANI Patent Attorney

Specialisations Mechanical structure, mechanical control, fluids, heat transfer

Following completion of his degree in Mechanical Engineering at Tohoku University, Mr. Toratani worked for 2 years at Nippon Steel in the Cold Rolling Group. In 2009, he pursued his career in a patent law firm as a patent engineer, where for 10 years he handled patent applications for domestic and foreign applicants in the field of mechanical engineering, particularly nuclear power plants, turbines, automotive parts, and semiconductor manufacturing equipment.

Mr. Toratani joined Nagato & Partners in 2021. He speaks Japanese and English.

Jacobus SONDERHOFF Qualified European Patent Attorney, Business Development

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

Following completion of his degree in physics (focus on astrophysics, digital image processing) at King’s College London, Mr. Sonderhoff worked for Siemens in Munich as a development engineer (optical quality control of memory chips) and then as a patent engineer in the patent department, followed by his independent work for European patent law firms and industry. In 2009, he decided to pursue his career in Tokyo at Sonderhoff & Einsel Law and Patent Office as a technical advisor for the electrical engineering section, followed by his work 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 business development with a focus on Asia. He joined us at Nagato & Partners in April 2021 and presently works in a business development role and as a qualified European Patent Attorney in an advisory capacity. Mr. Sonderhoff speaks German, English, Japanese and French.

Jacobus Sonderhoff