This map shows all the locations Sears once operated and what it has left today 

Sears, once the largest retailer in the U.S., has now filed for bankruptcy protection and said Monday morning it plans to close 142 more stores this year — adding to the stores the retailer already shuttered in 2018.

It isn't immediately known which stores the company plans to shutter. It once operated more than 3,500 locations across the U.S. under its namesake Sears brand and Kmart. Roughly 700 are still in business and it hopes to keep a portion open through this holiday season.

Sears has been shedding its real estate for years as one way to raise cash when the company has been in a pinch. In 2015, it spun off about 250 stores to form a real estate investment trust called Seritage. Within just the past two years, it has shut more than 700 stores.

Analysts say the company has opted to sell some of its more profitable locations from the get-go, leaving it with underwhelming assets.

As the retailer's real estate has dwindled, so has analysts' confidence the company can stay afloat. Sears has lost more than $11 billion since 2011. Its last profitable year was 2010.

Along with its bankruptcy filing, the company said Monday that Eddie Lampert's hedge fund, ESL Investments, is now in talks to buy "a large portion of the company's store base," while other assets are expected to be put up for sale in the next few months. Lampert had served as CEO of Sears for the past five years until Monday, when he resigned from the role effective immediately as part of the retailer's restructuring plan. He will remain chairman.

Lampert has a controlling ownership stake in Sears, with a 31 percent stake, according to FactSet. ESL Investments owns about 19 percent.

"Over the longer term, it is still unclear what Sears hopes to accomplish," GlobalData Retail Managing Director Neil Saunders said.

"In our view, there is no clear path to success," he said. "The group has tried to shrink its way to profitability for years to no avail, so it is hard to see why pursuing the same strategy under the auspice of Chapter 11 would result in a different outcome. Further asset sales may reduce debt, but they would not put the company on a sound financial footing nor would they solve the operating losses the group is racking up."

—Reporting by CNBC's Lauren Hirsch and Lauren Thomas. Data visualization by CNBC's John Schoen. Data on Sears locations was provided by AggData.com, a business location data service that specializes in retail locations.

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