Another reason why you need a good night’s sleep before executing large block trades with other people’s money.

On Thursday morning, a trader at Mizuho Securities tried to sell
610,000 shares at ¥1 each of a job recruiting company called J-Com,
which was having its public debut on the exchange. It had actually intended to sell 1 share at ¥610,000.

Even worse, the Tokyo Stock Exchange doesn’t let you cancel a trade once it’s in the system. Imagine the horror as this guy watches the market pounce on his mistake. By the end of the day, Mizuho lost $27 million and I’m pretty sure the poor guy who made the mistake is delivering pension checks on his bicycle to little old ladies in Hokkaido.