Photo, Masao Katsuyama

Masao Katsuyama

Baker & McKenzie (Gaikokuho Joint Enterprise)


Masao Katsuyama is a partner of the Firm’s Corporate / Mergers & Acquisitions Practice Group in Tokyo. Mr. Katsuyama worked in the Firm's Bangkok office from May 2012 to May 2014. He assisted many Japanese companies with investments in Thailand and other Southeast Asian countries.

Practice Focus

Mr. Katsuyama’s practice focuses on mergers and acquisitions, securities law and general corporate law. He has experience advising on the structuring of both Japanese and international mergers and acquisitions, as well as in the drafting of transaction documentation and due diligence. He also assists Japanese clients investing in Southeast Asian countries in collaboration with local lawyers.

Representative Legal Matters

  • Advised the acquisition by way of tender offer of a domestic listed company.
  • Advised a domestic listed company in relation to its acquisition by way of tender offer of a foreign company.
  • Assisted in various domestic integration and reorganization transactions in relation to both Japanese and international M&As.
  • Advised a Japanese domestic listed company in relation to the acquisition of a Thai private manufacturing company and execution of a shareholders agreement with a minority shareholder in Thailand.
  • Advised a Japanese domestic listed company in relation to a minority investment in a Thai listed company, and possible structures for incorporation of a joint venture company with the Thai company.
  • Assisted several Japanese domestic companies in conducting legal due diligence and preparing a legal due diligence report in relation to possible acquisition of Thai private companies.


  • Japan (2006)


  • New York University School of Law (LL.M.) (2011)
  • Kyoto University (LL.B.) (2005)


  • English
  • Japanese

Previous Offices

  • Bangkok

Co-author, "Navigating Business Expansion into Southeast Asia," Business Homu, Chuo Keizaisha, October 2012

Co-author, "World Legal & Business Guide No.19 Myanmar," Business Law Journal, LexisNexis, October 2012