 The oil and gas producer filed for Chapter 11 bankruptcy protection in a South Texas court on Sunday, after the company and its creditors agreed on the outlines of a restructuring plan that would eliminate 7 billion of debt. Chesapeake ticker: CHK plans to sell 600 million of new shares to a group of fund managers as part of that deal; its market capitalization was 116 million as of June 26, so the share sale will sharply devalue current shareholders stakes in the company. The stock was halted on Monday, and NYSE said it has started delisting proceedings, though the company said it believes that its shares will continue to trade through the process. 