Firm Profile > Sonderhoff & Einsel Law and Patent Office > Tokyo, Japan

Sonderhoff & Einsel Law and Patent Office
18th floor, 1-6-2 MARUNOUCHI, CHIYODA-KU
TOKYO 100-0005

Intellectual property: Independent local firms Tier 3

The ‘strong team of patent attorneys and lawyers’ at Sonderhoff & Einsel Law and Patent Office handles IP prosecution and enforcement as well as patent valuations, drafting of employee invention rules, licence negotiations, tax issues and patent infringement cases. The firm is well regarded for cross-border and multijurisdictional expertise in IP and patent matters. The practice is co-led by Felix-Reinhard Einsel, Hiroshi Morita, Shogo Matsunaga, Junichi Maekawa, Rui Ueshima, Hiroyasu Ninomiya and Hideo Nagashima.


‘We experienced a very high degree of reliability, receiving answers and services with short reaction time’

‘Exceptional language skills’

‘The professional standard is very high with regard to the technical and judicial skills’

‘Felix Einsel, Daisuke Endo and Rui Ueshima always had a strong technical understanding in the fields required with the helpful advice to reach our goals’

‘It’s a pleasure working together with Sonderhoff & Einsel’

‘Their broad knowledge also in German and European Patent Law makes it easier for us to discuss challenging questions in IP Law’

‘Felix Einsel and Masako Barnard provide excellent support in all kinds of IP issues’

‘Felix Einsel is an excellent bridge between Japan and his European clients who does the extra step to make us understand the particularities of Japanese patent prosecution and enforcement’

The firm:

Founded in Japan in 1910, Sonderhoff & Einsel Law and Patent Office has operated for more than 110 years in Japan as a leading firm with strong European ties. Having traditionally been among the first for German corporate clients seeking legal support in Japan, the firm presently assists a wide range of clients, not only from Japan but also from Europe, the US and China. In particular, recognizing the growing importance of China for its clients, Sonderhoff & Einsel Law and Patent Office works in close collaboration with Sonderhoff & Einsel (Beijing) Patent Agency Office, which was founded in 2012.

Today, the firm offers 15 attorneys at law, with qualifications from Japan, the US and Germany, as well as 26 Japanese patent attorneys and a Chinese patent attorney, supported by an in-house team of paralegals, technical specialists and translators. Its European roots are still evident under the leadership of patent attorney Felix-Reinhard Einsel, managing partner of the firm and the only European licensed as a patent attorney in Japan. In the past few years, our law practice has tripled in size and has added attorneys with experience at top global firms including a US-based international firm, a UK magic circle firm, as well as top five Japanese law firms.  We provide our clients with the personalized attention of a small firm coupled with our broad experience of dealing with cross-border transactions.

Areas of practice: 

With a 110-year history, the firm offers an outstanding comprehensive service to international clients. Emphasis is on all aspects of intellectual property law, including patents, utility models, designs, trademarks and unfair competition. The firm is also well-versed in global transactions with experience in a wide range of practice areas, such as general corporate and commercial transactions, mergers and acquisitions, labor and employment, life sciences, litigation and dispute resolution, finance, and aviation.

One of the competencies of its intellectual property practice is its reliable prosecution of patents covering a wide range of technology in the areas of mechanical engineering, electrical engineering and chemistry. For non-Japanese applicants, translations of patent applications into Japanese can be provided from English, German and Chinese, and for Japanese applicants, translations can be done from such languages into Japanese.

In its IP enforcement practice, Sonderhoff & Einsel counsels have developed a distinctive, cost-effective anti-counterfeiting practice that makes it a leading firm in the country. Certain patent cases handled by Sonderhoff & Einsel have become cornerstone cases in the field.

Department Name Email Telephone
Managing Partner, Patent Attorney (Patent, Trademark and Design Prosecution) Mr. Felix-Reinhart Einsel +81-3-5220-6500
Managing Partner, Attorney at Law (Regulatory and Finance) Mr. Keiji Isaji +81-3-5220-6500
Senior Partner, Attorney at Law (Commercial Transactions and Dispute Resolution) Mr. Atsushi Yamashita +81-3-5220-6500
Senior Partner, Patent Attorney (Patent, Trademark and Design Prosecution) Mr. Morita, Hiroshi +81-3-5220-6500
Partner, Attorney at Law, Patent Attorney (IP Infringement Litigation and Dispute Resolution, Anti-counterfeiting, and Labour) Mr. Shogo Matsunaga +81-3-5220-6500
Photo Name Position Profile
Mr Takashi Akabane  photo Mr Takashi Akabane Patent Attorney
Ms Masako Barnard  photo Ms Masako Barnard Patent Attorney
Dr Georg Bissen  photo Dr Georg Bissen Attorney at Law (Germany)
Mr Felix-Reinhard Einsel  photo Mr Felix-Reinhard Einsel Managing Partner. Prosecution of patents, designs and trademarks, oppositions, invalidations, expert opinions…
Mr Daisuke Endo  photo Mr Daisuke Endo Patent Attorney
Mr Keiji Isaji  photo Mr Keiji Isaji Managing Partner. Civil and criminal litigations; finance regulatory and litigation; white collar…
Mr Jun Ito  photo Mr Jun Ito Patent Attorney
Ms Yukie Kamiya  photo Ms Yukie Kamiya Patent Attorney
Mr Tomoyuki Kawanishi  photo Mr Tomoyuki Kawanishi Attorney at Law
Ms Yasuyo Kimura  photo Ms Yasuyo Kimura Attorney at Law
Mr Takuya Kuno  photo Mr Takuya Kuno Patent Attorney
Ms Saori Maekawa  photo Ms Saori Maekawa Patent Attorney
Mr Junichi Maekawa  photo Mr Junichi Maekawa
Mr Shogo Matsunaga  photo Mr Shogo Matsunaga Partner, Attorney at Law, Patent Attorney
Mr Hiroshi Morita  photo Mr Hiroshi Morita Patent Attorney
Mr Hideo Nagashima  photo Mr Hideo Nagashima Patent Attorney
Ms Ayuko Nemoto  photo Ms Ayuko Nemoto partner, Attorney at Law
Mr Hiroyasu Ninomiya  photo Mr Hiroyasu Ninomiya Patent Attorney
Mr Makoto Ohsugi  photo Mr Makoto Ohsugi Attorney at Law
Mr Akinori Ohta  photo Mr Akinori Ohta Patent Attorney
Mr Reiko Otani  photo Mr Reiko Otani Patent Attorney
Mr Kengo Sakai  photo Mr Kengo Sakai Kengo Sakai’s practice focuses on general corporate matters and commercial transactions, financial…
Mr Ryoichi Shino  photo Mr Ryoichi Shino Patent Attorney
Mr Takeshi Shinoda  photo Mr Takeshi Shinoda Patent Attorney
Mr Shuichi Sumiyoshi  photo Mr Shuichi Sumiyoshi Patent Attorney
Mr Hidehiko Suzuki  photo Mr Hidehiko Suzuki Attorney at Law
Mr Yoshihiro Takahashi  photo Mr Yoshihiro Takahashi Patent Attorney
Mr Ryo Takamatsu  photo Mr Ryo Takamatsu Attorney at Law
Mr Utahito Takeuchi  photo Mr Utahito Takeuchi Patent Attorney
Mr Grant Tanabe  photo Mr Grant Tanabe Partner, Attorney at Law
Ms Hisako Tanaka  photo Ms Hisako Tanaka Patent Attorney
Mr Shohei Teramae  photo Mr Shohei Teramae Attorney at Law
Mr Shoji Torino  photo Mr Shoji Torino Patent Attorney
Ms Ayano Ueda  photo Ms Ayano Ueda Attorney at Law
Mr Rui Ueshima  photo Mr Rui Ueshima Patent Attorney
Mr Naoki Watanabe  photo Mr Naoki Watanabe Attorney at Law
Ms Xiaofen Wu  photo Ms Xiaofen Wu Chinese Patent Attorney
Mr Hiroyuki Yajima  photo Mr Hiroyuki Yajima Patent Attorney
Mr Atsushi Yamashita  photo Mr Atsushi Yamashita Senior Partner, Attorney at Law
Ms Wakako Yamazaki  photo Ms Wakako Yamazaki Patent Attorney
Lawyers : 15
Patent attorneys : 26
Tax consultants : 3
German Chamber of Commerce and Industry in Japan
Swiss Chamber of Commerce and Industry in Japan
German Japanese Lawyers' Association