The investigation into the bankruptcy of MF Global has been expanded to include CME Group, sources said. The Commodity Futures Trading Commission is looking into whether CME's supervisory efforts were sufficient, according to sources. "Given the issues involved, we welcome and expect the CFTC's investigation as a natural part of this process," a spokeswoman for CME Group said. "We are confident the CFTC's review will determine we did everything right within our regulatory power. The system did not fail; the firm broke the law by misusing customer funds." CME has not been accused of any wrongdoing.