About our Firm

Leadz Law Office

Leadz Law Office is an Osaka-based law firm providing a comprehensive range of services including M&A and company reorganization, tax planning, tax dispute resolution and family business management. Prior to founding the firm in July 2018, the managing partner, Hideto Nagai served as an administrative judge at National Tax Tribunal, Osaka office.
We work closely with many tax attorneys who are former tax enforcement specialists and are able to develop creative approaches to problem solving.


We provide a comprehensive range of services to clients. Our services include:

Dispute Resolution
– Civil disputes
– Tax disputes
– Intellectual properties (patent, trademark, design, copyright, trade secrets, etc.) disputes

Tax Matters/ Tax Planning
– Tax audit defense and appeals
– Tax planning supports

Business Succession/ Wealth Management
M&A and Reorganization
– Planning
– Due diligence
– Documentation

General Corporate
– Governance
– Finance
– Antitrust law
– Labor law


Leadz Law Office

Minami-Morimachi Park Building, 7th Floor, 5-1-3 Nishitenma
Kita-ku, Osaka 530-0047 Japan

Telephone: (81) 6-6809-6233
Facsimile: (81) 6-6809-6279




Hideto Nagai — Attorney at Law & Certified Tax Accountant

Hideto Nagai, a.k.a. Ben Nagai, is a founder of Leadz Law Office. Prior to founding Leadz Law Office, Mr. Nagai served as an administrative judge (2015-2018) at National Tax Tribunal, Osaka office. He has extensive experience in international and domestic tax issues and estate tax issues.
Before serving as an administrative judge, Mr. Nagai worked at Morrison & Foerster LLP, Tokyo office (formerly also known as Ito & Mitomi Law Office) and Los Angeles office where he specialized in intellectual properties disputes and represented American, Asian and Japanese clients in IP litigation matters and civil antitrust litigation matters. Mr. Nagai also has a broad range of experience in international business transactions, corporate matters (including labor laws, advertising laws, personal information protection laws, IP transactions), family business, real property and trust and estate law.
Additionally, Mr. Nagai has several years experience as a financial analyst and financial market investor at a general trading company, sogo shosha.
Mr. Nagai is a member of the Osaka Bar Association, the Japan Federation of Bar Associations, the Japan Federation of Certified Public Tax Accountants’ Associations and the Japan Tax Jurisprudence Association.
Mr. Nagai serves as an adjunct lecturer of legal writing in civil practice at Kyoto University Law School since 2017.
Mr. Nagai has been the Vice Chairman of the Osaka City Administrative Appeals Committee (Tax Subcommittee) since 2020.


– Kyoto University (LL.B., 1998)
– Doshisha University Law School (J.D., 2006)
– University of Southern California Gould School of Law (LL.M., 2013)

Bar Admission

– Japan (2007)


Japanese, English 


Naoki Morimura — Attorney at Law

Naoki Morimura is an associate of Leadz Law Office. 
Mr. Morimura is a member of the Osaka Bar Association and the Japan Federation of Bar Associations.
Mr. Morimura has extensive knowledge in real estate law, sports law, labor law and family law.


– Kindai University (LL.B.)
– Kindai University Law School (J.D.; summa cum laude; Dean’s Award)