Sears shares tumbled as much as 14 percent on Monday, piling onto declines that have sent the value of its stock more than 30 percent lower since Wednesday.
The stock later recovered its losses, but still ended the day about 7.6 percent lower.
The precipitous drops, which pushed the chain's shares to fresh lows since its merger with Kmart more than a decade ago, come as Kmart is laying off employees at many of its U.S. stores that will stay open past the spring. Sears currently operates roughly 800 Kmart stores, but is in the process of closing 108 of them.
Sears spokesman Howard Riefs said the layoffs are part of the company's annual review of store staffing needs. He declined to share the number of employees that will be impacted, or how that number compares with past years. The layoffs were first reported by Business Insider.
"Some stores won't have any changes tied to this action and some will have reductions or additions of full-time positions," Riefs told CNBC in a statement. "Eliminating positions is never easy decisions to make, and we don't take it lightly as we recognize the valuable contributions affected associates make to the company."
Sears shares ended the day at $6.86, down nearly $190 from the all-time high of $195.18 they hit in April 2007.
The department store chain has made a number of financial maneuvers over the past few months as it aims to inject cash into its business. They include selling its Craftsman label to Stanley Black & Decker and closing 150 unprofitable Sears and Kmart stores.
Yet ratings firms are growing more pessimistic about the company's future. In a note last week, Fitch Ratings downgraded Sears' senior unsecured notes, and said it anticipates the retailer burned through $1.6 billion in cash in 2016. Meanwhile, the agency predicts Sears will report a loss of $950 million to $1 billion in 2016 and 2017.
That report came a few days after Moody's downgraded Sears' corporate rating.
"Although Sears has been able to fund its continued cash shortfalls through planned asset monetization, and additional financings, a meaningful business turnaround in fiscal 2017 is critical given the continued reduction of its asset base," Moody's Vice President Christina Boni said in a statement at the time.
Sears has already said that same-store sales at Sears and Kmart declined between 12 and 13 percent in November and December.