Mizuho Securities Co. is the brokerage arm of Mizuho Financial Group. Mizuho Financial Group (みずほフィナンシャルグループ Mizuho Finansharu Gurūpu), (TYO: 8411) established in January 2003, is one of the largest financial services companies in the world. ...

On 8 December 2005 an order from Mizuho Securitites Co. to sell 1 share of J-Com Co at 610,000 yen was mistakenly entered as a sale of 610,000 shares at 1 yen. Problems at the Tokyo Stock Exchange meant that Mizuho securities were unable to cancel the order for 10 minutes and in the meantime traders from domestic and international investment banks bought large amounts of the wrongly priced shares. Mizuho Securities lost about $347 million on the mistake. December 8 is the 342nd day (343rd in leap years) of the year in the Gregorian calendar. ... The Tokyo Stock Exchange (東京証券取引所 Tōkyō Shōken Torihikijo, abbreviated TSE) is the worlds second-largest stock exchange market. ...

The error, and particularly the Tokyo Stock Exchange's perceived poor handling of it, raised some questions about Japan's readiness to deal with the increasingly complex financial markets. The Tokyo Stock Exchange (東京証券取引所 Tōkyō Shōken Torihikijo, abbreviated TSE) is the worlds second-largest stock exchange market. ...