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島田 まどか
島田 まどか


  • Partner
  • Tokyo
  • "She is a very diligent lawyer. She's across all aspects of competition law and handles domestic and international merger control mandates." A further source says: "Ms Shimada is a very knowledgeable, hands-on competition lawyer who can turn around matters which others have given up on."

    Chambers, Competition/Antitrust - Japan (Asia-Pacific 2022)

Madoka is focusing on the antitrust and competition law area, providing a broad range of advice in the field of competition law, with a wealth of experience in, among other things, cross-border transactions. She also has strength in trade secret cases.

Madoka advises clients on various matters of competition law, including domestic and international cartels, bid-rigging, M&A transactions, investigations by the JFTC, leniency applications and general antitrust law compliance. She is especially active in cross-border transactions. She has represented clients in connection with investigations into various global cartels, involving air cargo, marine hoses, TFT-LCDs, airlines, and bearings, and also in various merger-control cases, including a vertical integration between semiconductor equipment manufacturers, and major global merger transactions in the chemical and pharmaceutical industries. She has particular strength and experience handling IT-industry mega deals. Madoka is also active in advising in the international trade area, in particular, government procurement and export control. In addition, she advises on laws preventing unfair competition, including trade secret cases. She served as lead counsel to Nippon Steel Corporation in multinational trade secret litigation against POSCO (a South Korean steel company), a landmark case in this area, and successfully negotiated a favorable settlement for her client. She was a member of the Subcommittee on Unfair Trade Policies and Measures of the Industrial Structure Council at the Ministry of Economy, Trade and Industry from 2013 to 2023.

Representative Work

Awards & Rankings





Kennedy School of Government, Harvard University (M.P.A.)
Harvard Law School (LL.M.)
The University of Tokyo (LL.B.)

Professional Experience

Mitsui, Yasuda, Wani & Maeda