Nomura Holdings named Koji Nagai as its new CEO on Thursday and said it was likely more insider trading cases would come to light in a scandal that forced Kenichi Watanabe to quit as head of Japan's top investment bank.
The management shake-up was confirmed in a news conference at the end of a dramatic day in Tokyo that also saw Watanabe's top lieutenant, Takumi Shibata, resign over leaks of insider information to clients of its securities unit in 2010.
Nagai, a three-decade company veteran, took over that unit in April as part of a management reshuffle.
In an update on its own investigation into the scandal, Nomura said there was a "high possibility" more insider trading leaks would be uncovered beyond those reported to the Financial Services Agency.
The resignations of Watanabe and Shibata, Nomura's chief operating officer, and their replacement by Nagai and Atsushi Yoshikawa, the head of its US operations, would take effect on 1 August, the bank said.
The departure of the architects of Nomura's takeover of the Asian and European assets of Lehman Brothers raises questions about the future of the global expansion strategy they pursued.
Nagai said he would map out a "new global strategy", adding he had no intention of dropping the ambition of being a global investment bank centred in Asia.