The effective date of the merger was postponed a couple of times due to the financial crisis.

[2] In 2004, the Polaris Capital Group was divested, focusing on private equity investment.

[3] Mizuho Securities is involved in bond and stock trading, debt and equity financing, and advisory services for structured finance; its clients include financial institutions, public corporations, and institutional investors or firms.

[5] During the early 2000s, it was considered to be one of the "big four" firms that controlled a large portion of Japanese trading.

[6] In December 2005, an employee at Mizuho Securities placed an erroneous sell order of J-COM Co., Ltd. shares on the Tokyo Stock Exchange,[7] resulting in a loss of approximately ¥40.7 billion.