Nasdaq OMX Group Inc. had to close the six largest U.S. options exchange for over five hours today because of technical error. In a statement Nasdaq said, "significant increases in order entries inhibited the system's ability to accept orders and disseminate quotes" and the market was closed for the rest of the day. This is a bad look for the Nasdaq which recently lost the big for Twitter's IPO, its important for their markets to run. In September this markets handled close to 8% of all options trading.