INDIVIDUAL PROFILE
Atsushi Oishi

Atsushi Oishi

High Net Worth 2026

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Mori Hamada
 Mori Hamada

Ranked in 1 practice area

Private Wealth Law: Bengoshi

Japan

4 years ranked

Contributions and articles

1 Global Practice Guides

About

Provided by Mori Hamada

High Net Worth

Practice Areas

M&A (M&A / Reorganizations / Capital and Business Alliances, Private Equity, Cross-Border M&A); Tax (Tax Investigations and Disputes, Tax Planning); Wealth Management; Dispute Resolution; Corporate Law (Corporate and Commercial Disputes)

Career

Background

The University of Tokyo (LL.B., 1996); New York University School of Law (LL.M., 2003); Weil, Gotshal & Manges, New York (2003-2004)

Major Activities

Member of Task Force on Management Buy Out and Other Transactions, organized by Ministry of Economy, Trade and Industry (2007); Member of Expert Committee on Anti-Tax Haven Legislation and Intangible Assets, organized by Ministry of Economy, Trade and Industry (2013); Invited Researcher at Global Family Business Research Institute, Waseda University (2016-); Member of PB Professional Ethics Review Committee, The Securities Analysts Association of Japan (2018-); Member of PB Education Committee, The Securities Analysts Association of Japan (2018-); Member of Study Group on Family Business Governance, Ministry of Economy, Trade and Industry (2025-)

Professional Memberships

admitted in Japan, 1998; New York, 2004; Japan-Licensed Tax Accountant (2006); Certified as Support Agencies for Business Innovation (2018)

Chambers Review

Provided by Chambers

Chambers High Net Worth

Private Wealth Law: Bengoshi - Japan

Band 1
Individual Editorial
Atsushi Oishi advises on a wide array of private wealth matters, particularly in business succession and tax investigations. He is also well known for his sophisticated tax and estate planning techniques as well as being knowledgeable on matters related to M&A for both domestic and international clients.
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Strengths

Provided by Chambers

  • Atsushi is a highly reliable attorney with extensive experience in wealth management, and he provides precise advice.

    Private Wealth Law: BengoshiChambers High Net Worth

  • Atsushi has a wide range of experience, including on legal and tax matters related to family governance and private wealth. He is arguably one of the best lawyers in Japan.

    Private Wealth Law: BengoshiChambers High Net Worth

  • Atsushi is very clear and concise in his advice. It is succinct and to the point, and he can digest complex information and then advise a layperson well.

    Private Wealth Law: BengoshiChambers High Net Worth

Ranked Individuals at Mori Hamada (2)

Japan

All Contributions (1)

Provided by Mori Hamada

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