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五十嵐 誠
五十嵐 誠


  • Partner
  • Tokyo

Extensive experience as counsel to fund/asset management industry over 30 years Providing specialist advice in respect of fund raising and placement of various types of investment funds

He plays a vital senior role within the firm’s fund/asset management practice group which he has set up. With the resources of Japan’s largest law firm, he and his colleagues are able to assist clients in all aspects of large-scale buyout and financing transactions, including due diligence, financing and tax matters, strategy and compliance issues, and regulatory filings. Over 30 years, he has extensive experience as counsel to fund promoters, investment managers, placement agents, pension funds and various other financial institutions, providing specialist advice in respect of fund raising and placement of buyout funds, turnaround or mezzanine types of private equity funds, hedge funds, infrastructure funds, real estate funds and any other types of collective investment scheme. He also serves as counsel to investment fund institutions and advisers, financial advisers, banks and other senior lenders, advising on buyout loans and other debt/equity financing matters. He is a 1987 LLB graduate of the University of Tokyo and received an LLM from Harvard Law School in 1994. He has been a member of the Japanese and New York Bars since 1989 and 1995 respectively, and fluent in both English and Japanese. He joined the firm in 1989 and has been a partner from 1998. He spent one year on secondment at Cravath, Swaine and Moore, New York (1994 to 1995) and served as lecturer on finance law at Keio Law School, Tokyo (2004 to 2013) and as corporate auditor at Mitsubishi UFJ Morgan Stanley Securities Co., Ltd. (2014 to 2022).

Awards & Rankings



Harvard Law School (LL.M.)
The University of Tokyo (LL.B.)

Professional Experience

Corporate auditor, Mitsubishi UFJ Morgan Stanley Securities Co., Ltd.
Lecturer, Keio University Law School 
Cravath, Swaine & Moore, New York