Nasdaq unwavering on paybacks for faulty Facebook launch NEW YORK (Reuters) - Nasdaq OMX Group Inc stands by its $62 million compensation plan for firms harmed in Facebook Inc's glitch-ridden market debut and is prepared to defend against any potential litigation related to it, Lee Shavel, the company's chief financial officer, said on Monday. The company has received mixed reviews of the plan, filed with regulators in late July. Top retail market-making firms Citadel Securities and Knight Capital Group voiced support, while UBS AG and Citigroup strongly criticized the plan for not going far enough, and asked the U.S. Securities and Exchange Commission reject it. "Clearly there are differences of opinion, and some are more negative on the proposal," Shavel said at the Barclays Global Financial Services Conference in New York. We continue to believe ... that this addresses the issues that we identified in a very fair, reasonable, and objective manner. At stake is the extent to which an exchange can be liable for technical slip-ups. U.S. exchanges match hundreds of billions of dollars of securities transactions every day. The New York-based exchange operator had originally offered to reimburse up to $40 million in total, with the majority of that in the form of trading rebates. But after a barrage of criticism from trading firms and other exchanges, it increased the amount in its proposal to $62 million, all in cash. Total losses from the May 18 IPO at market-making firms and brokers are estimated at more than $500 million. UBS has said it was looking at its legal options to recover the full extent of the more than $350 million it lost. Shavel said Nasdaq has "robust legal and factual defenses" with regard to any potential litigation. Facebook's eagerly anticipated IPO, which raised $16 billion, was initially delayed by 30 minutes due to a technical glitch at Nasdaq. The exchange then made the decision to get the stock trading by using a secondary system that ended up leading to delays in many clients orders and confirmations, costing some investors and traders steep losses as the stock price dropped after an initial gain. Under the compensation plan, firms that take part must give up their right to sue the exchange for losses associated with the IPO. Knight, which recently had its own technical glitch that cost it $440 million and nearly bankrupted the firm, said in a letter to the SEC that while it supports Nasdaq's efforts, the condition of having to waive the right to sue would "set a harmful precedent." Nasdaq expects a ruling on the plan by the SEC in the fourth quarter. "We are certain that they are giving it all of their attention at this point," Shavel said. Shares of Nasdaq were down 0.3 percent at $23.66 on Monday afternoon. Reporting by John McCrank; Editing by Tim Dobbyn and Alden Bentley