The cost of Nasdaq's bungling of the Facebook IPO has shot up $357 million.
Swiss banking giant UBS says it lost that much from the stock exchange's "gross mishandling" of the May 18 initial public offering, the largest ever for a U.S. technology company.
In a sharply worded statement, UBS said it ultimately purchased "far more shares than our clients had ordered" because Nasdaq's trading system failed to confirm UBS traders' orders.
"UBS's loss resulted from Nasdaq's multiple failures to carry out its obligations, including both opening the Facebook stock for trading and not halting trading in the stock during the day," UBS said. "We will take appropriate legal action against Nasdaq to address its gross mishandling of the offering and its substantial failures to perform its duties."