Article is behind a paywall. Mt. Gox, the struggling Japanese bitcoin exchange, has filed for bankruptcy protection in a U.S. court to stop custome

Article is behind a paywall. Mt. Gox, the struggling Japanese bitcoin exchange, has filed for bankruptcy protection in a U.S. court to stop customers from freezing any of the company's assets that are located on U.S. soil. Lawyers put MtGox Co. Ltd. into Chapter 15 protection in Texas on Sunday, stating that a potential class-action lawsuit in Illinois could get in the way of reorganization efforts that are taking place in the company's home country. Mt. Gox, an exchange for buyers and sellers of the digital currency known as bitcoin, halted customer withdrawals on Feb. 7, later stating that it lost almost 750,000 of its customers' bitcoins and around 100,000 of its own. "This theft or disappearance is currently the subject of an intense investigation which required Mt. Gox to devote most of its resources," Mt. Gox lawyers wrote in court papers. In the potential class-action lawsuit, lawyers are trying to round up U.S. residents who paid a fee to Mt. Gox to buy, sell or trade bitcoin, according to court papers filed in U.S. Bankruptcy Court in Dallas. As part of that lawsuit, lawyers are expected to ask Tuesday during a court hearing for the power to freeze any of Mt. Gox's U.S. assets, which include any servers or other computer equipment that stores customer information about bitcoins. It is unclear what assets—if any—Mt. Gox has in the U.S. Still, the U.S. bankruptcy halts existing lawsuits, at least temporarily. More specifically, Chapter 15 of the U.S. Bankruptcy Code is available to foreign companies that have sought protection of their home courts. Mt. Gox filed for bankruptcy protection in Japan last month. Participating in the U.S. lawsuits at this point "would wastefully divert resources away from" the Japanese bankruptcy, Mt. Gox lawyers wrote in court papers. The company's lawyers said that Mt. Gox's debts totaled 6.5 billion yen ($63.9 million) versus assets of 3.84 billion yen. Mt. Gox hired the Baker & McKenzie law firm to represent it in bankruptcy. The company's case, numbered 14-31229, has been assigned to Judge Stacey G. Jernigan. —Jacqueline Palank contributed to this article. Write to Katy Stech at katherine.stech@wsj.com