Awards
Keiji Tonomura
Partner
Tokyo Office
- Languages
- Japanese, English
- Qualifications
- 2007(-2012), 2014, Japan (Dai-Ichi Tokyo Bar Association)
Keiji Tonomura is a partner at Nagashima Ohno & Tsunematsu. His practice focuses on mergers and acquisitions and intellectual property and information technology related transactions and counseling. He has extensive experience representing global and local clients on mergers and acquisitions, joint ventures, strategic alliances and other complex business transactions as well as data security and data privacy issues across a range of industry sectors, with a particular focus on the TMT (technology, media and telecoms) sectors and the new business fields generated by the development of emerging technologies, such as sharing economy, Fintech, IoT and AI. He also regularly provides global and local clients with corporate governance related and other general corporate advice.
Practice Areas
Education/Professional Experience
- 2004
- Kyoto University (LL.B.)
- 2006
- Kyoto University Law School (J.D.)
- 2007 -
- Nagashima Ohno & Tsunematsu
- 2013
- Columbia Law School (LL.M., Harlan Fiske Stone Scholar)
- 2013 - 2014
- Kirkland & Ellis LLP, Chicago
- 2018 - present
- Partner, Nagashima Ohno & Tsunematsu
- 2025 - present
- Working Group Member of Liberal Democratic Party Headquarters for the Promotion of Digital Society “AI and web3 Subcommittee”
Awards
Seminars
-
July 15, 2026 (Wed) -AI Seminar 2026 : Part 2 Legal Issues and Governance of AI Agents
- Keiji Tonomura
- Yoshiteru Matsuzaki
Online (On-Demand)
- Technology
- AI and Robotics
- Internet/IT Services/Cloud
-
June 18, 2026 (Thu) -AI Seminar 2026 : Part 1 “Guide on the Interpretation and Application of Civil Liability in AI Utilization” —Including Perspectives on Agent AI and AI Governance”
- Keiji Tonomura
- Takahiro Hatori
- Yuki Matsumiya
Online (On-Demand)
- Technology
- AI and Robotics
- Dispute Resolution
-
February 6, 2026 (Fri) 15:00 - 17:00[Law Firm x Third Party Certification Body x Consulting Firm] Implementing AI Governance from Three Perspectives: Navigating Regulatory Trends and International Standards (ISO)
- Keiji Tonomura
- Yuta Katayama (Re-grit Partners)
Nagashima Ohno & Tsunematsu Tokyo Office
- Technology
- AI and Robotics
-
October 3, 2025 (Fri) 14:30 - 17:30Recent Legal Topics in Technology Field 2025
- Keiji Tonomura
- Yukiko Konno
- Minh Thi Cao Koike
Nagashima Ohno & Tsunematsu Tokyo Office
- Technology
- AI and Robotics
- Internet/IT Services/Cloud
Publications
-
Articles
The Legal 500: 10th Edition TMT Country Comparative Guide – Japan
(August 2026)
Keiji Tonomura, Minh Thi Cao Koike, Anju Yamamoto, Iroha Honda (Co-author)
- Technology
- Finance
- Data and IoT
- AI and Robotics
-
Articles
Chambers Global Practice Guides TMT 2026 Japan – Trends & Developments
(February 2026)
Keiji Tonomura, Akira Komatsu, Minh Thi Cao Koike, Yuki Matsumiya (Co-author)
- Technology
- Digital Transformation (DX)
- Digital Platform
-
Articles
Chambers Global Practice Guides Fintech 2026 Japan – Trends & Developments
(April 2026)
Keiji Tonomura, Shu Sasaki, Kazuyuki Ohno, Otoki Shimizu (Co-author)
- Technology
- Finance
- FinTech
-
Articles
TMT: Recent Trends of AI in Japan
(April 2026)
Keiji Tonomura, Akira Komatsu (Co-author)
- Technology
- AI and Robotics
- Telecommunications
Featured Topics
Topics
-
Announcements
Keiji Tonomura appointed as the Expert Member of Study Group on Data Contract Guidelines in Agricultural Sector, Ministry of Agriculture, Forestry and Fisheries.
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Announcements
Keiji Tonomura appointed as a member of Working Group for Study Group on Data Contract Guidelines, Ministry of Economy, Trade and Industry.
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Announcements
Announcing New Partners and Counsel of NO&T
