Ken is managing partner of the Tokyo office and head of the office’s 50 lawyer M&A team. His practice focuses on the representation of high-technology companies in acquisitions, joint ventures, and strategic alliances.

Ken is consistently ranked as one of the leading U.S. lawyers in Japan. Among other notable accomplishments, he is the only lawyer to be ranked as a “Star Individual” for M&A in Japan (the level above Band 1) by Chambers Global for twelve consecutive years (2011 - 2022 editions); he was also ranked in the Band 1 category for the prior decade.

Ken has spent his entire career with MoFo and has practiced in Japan for over 25 years, serving as our Tokyo managing partner for the last 20 years.

Ken has appeared on CNBC and PBS’s Nightly Business Report in their coverage of Japanese legal developments, as well as on the cover of The American Lawyer in its survey of global law firms. He was also recognized by The American Lawyer as “Dealmaker of the Week” for his work on SoftBank’s $21.6 billion acquisition of Sprint, a transaction that was named the Global M&A Deal of the Year by The American Lawyer and also for his work on Hitachi’s $5 billion sale of its hard disk drive business to Western Digital.

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Ken’s recent notable awards include:

  • Star Individual for Japan: Corporate/M&A (Chambers Global 2022)
  • Star Individual for Japan: Corporate/M&A (Chambers Asia-Pacific 2022)
  • Hall of Fame for Japan: Corporate and M&A (The Legal 500 Asia Pacific 2022)
  • Market Leader for Japan: M&A (IFLR1000 2020)
  • Corporate, M&A Law, Private Equity, Private Funds and Venture Capital Law [The Best Lawyers in Japan (Recognized since 2009)]
  • Foreign Lawyer of the Year (Asian Legal Business (ALB) Japan Law Awards 2018)
  • Tokyo Managing Partner of the Year (Asian Legal Business (ALB) Japan Law Awards 2017)
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  • Represented SoftBank Group Corp. and SoftBank Vision Fund in the proposed $65 billion sale of UK-headquartered multinational semiconductor and software design company Arm Limited to U.S. chip company NVIDIA.

  • Represented SoftBank Group Corp., Sprint’s controlling shareholder, on the landmark merger of Sprint and T-Mobile US, Inc. The total implied enterprise value for Sprint is approximately $59 billion and the aggregate implied enterprise value for the combined company in the all-stock transaction is approximately $146 billion.

  • Represented SoftBank in its £24.3 billion ($31.4 billion) acquisition of UK-based semiconductor and software design company ARM Holdings. The transaction was the largest-ever cross-border acquisition by a Japanese company (and the largest-ever cash acquisition of a UK company).

  • Represented SoftBank in its $21.6 billion acquisition of a 78% interest in U.S. wireless operator Sprint. The transaction was the largest U.S. M&A transaction of 2012 and, when announced, the largest cross-border acquisition by a Japanese company (now second to SoftBank’s acquisition of ARM Holdings in 2016).

  • Represented Toshiba Corporation in the $18 billion sale of its wholly owned subsidiary Toshiba Memory Corporation to a consortium led by Bain Capital, the largest private equity deal ever undertaken in Asia.

  • Represented SoftBank in its $7.7 billion primary and secondary investment as part of a $9.3 billion sale of stock by Uber. This is the largest-ever private secondary transaction in the technology space.

  • Represented SoftBank, Alibaba’s largest shareholder, in Alibaba’s initial public offering of American Depository Shares on the New York Stock Exchange. The IPO was the largest-ever IPO on the NYSE, initially valuing Alibaba at $168 billion.

  • Represented SoftBank in the restructuring of Alibaba’s financial services businesses. The restructuring, undertaken in preparation for Alibaba’s IPO, secured and extended Alibaba’s long-term economic participation in Alipay and its broader financial services business.

  • Represented SoftBank in a three-way transaction between SoftBank, Yahoo, and Alibaba, in which Alibaba repurchased half of Yahoo’s shares in the company for $7.6 billion, the parties restated their shareholders agreements, and SoftBank became Alibaba’s largest shareholder, the largest-ever investment/M&A transaction between a Japanese company and Chinese company.

  • Represented Hitachi in the $4.8 billion sale of its hard disk drive subsidiary, Hitachi Global Storage Technologies (HGST), to Western Digital. At the time of sale, HGST had over 40,000 employees worldwide and was one of the world's leading HDD manufacturers.

  • Represented Hitachi and Hitachi Appliances on their formation of a global air conditioning joint venture with Johnson Controls, integrating the companies’ market-leading HVAC businesses. Johnson Controls obtained a 60 percent ownership stake in Hitachi Appliances’ more than $2.6 billion global air conditioning business.

  • Represented TDK in the formation of its $3 billion joint venture with Qualcomm to provide industry-leading radio frequency front-end (RFFE) modules and RF filters for mobile devices, drones, robotics, and automotive applications.

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