Mt. Gox, once the worlds largest bitcoin exchange, filed for U.S. bankruptcy protection in Dallas late Sunday, a move that will temporarily halt U.S. legal action against the Japanese company. Mt. Gox, which filed for bankruptcy protection in Japan in February, said without U.S. protection it would spend substantial funds defending itself against a U.S. lawsuit seeking class action status that was filed in federal court in Chicago. A hearing in Dallas was scheduled for 1:30 p.m. local time on Monday to consider Mt. Goxs request to stay pending lawsuits against the company. The plaintiff leading the Chicago lawsuit was scheduled on Tuesday to ask a federal judge to freeze Mt. Goxs U.S.-based servers and other computer equipment and to set up a trust over Mt. Goxs assets.