Edward S. Lampert, who leads the struggling retailer, has taken control of valuable real estate and businesses. The hedge fund manager Edward S. Lampert has spent the last 14 years steering Sears as it spun off businesses, took on debt and, this week, filed for bankruptcy protection. His hedge fund, ESL Investments, appears to have racked up a much more modest loss than the company’s Chapter 11 bankruptcy filing would suggest, according to corporate filings and interviews with analysts and investors. ESL’s nearly 50 percent stake in Sears will probably be wiped out in bankruptcy.