Filing a rebuff to hedge fund manager Eddie Lampert whose fund, the largest equity holder and major debt holder in retailer, had been pushing a debt restructuring proposal Sears Holdings Corp, the struggling US chain owned by hedge fund manager Eddie Lampert, is preparing for a bankruptcy filing as soon as Sunday, according to a person familiar with the plan. The company faces a critical debt maturity next week. The plan to file for Chapter 11 protection is a rebuff to Lampert, whose fund, ESL Investments Inc, is the retailer’s biggest equity holder and a major debt holder.