Kosuke Hamaguchi joined Nagashima Ohno & Tsunematsu in 2006 and has been a partner since 2017. His practice mainly involves public and private M&A transactions and corporate governance. He also regularly advises clients on corporate crisis management and foreign investment control. He has intensive experience in cross-border matters and is co-heading the African practice of the firm. He earned his LLB and LLM from the University of Tokyo in 2001 and 2003 respectively, and his LLM from the University of Virginia School of Law in 2012. He worked as a visiting lawyer at Sullivan & Cromwell from 2012 to 2013, and is admitted to the bar in Japan and New York.
Publications
Co-author of the Japan chapter in the Global M&A Law Guide , published 28 April 2026 , alongside Daisuke Ikukawa .