Mt. Gox Co., once the world’s largest bitcoin exchange, won approval of its U.S. bankruptcy filing, giving a boost to a Japanese investigation into the disappearance of 650,000 units of the digital currency, Bloomberg Businessweek reported. U.S. Bankruptcy Judge Stacey G. Jernigan said today in Dallas she has “ample legal authority” to accept the U.S. filing and recognize Mt. Gox’s Japanese bankruptcy as the foreign main proceeding. The ruling empowers the company’s Japanese trustee to examine witnesses, gather and review evidence, and oversee assets in the U.S., such as servers. “This is really going to be all about the customers,” who make up almost all of the creditors, and trying to get them a recovery, Jernigan said at a hearing. Mt. Gox in February sought court protection in Japan after losing 850,000 bitcoins, then valued at about $473 million. Customers lost about 750,000 and Mt. Gox lost about 100,000 of its own. The company later found 200,000 in an old-format digital wallet.