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What: Shares of retailer Sears Holdings (Nasdaq: SHLD) have been rallying since the get-go, up as much as 11% at one point today despite no company-specific news.

So what: Retail sales at Sears have been weaker than many of its peers, so it’s not a shock that Sears Holdings boasts a very large number of short-sellers. As of Sept. 15, according to The Wall Street Journal, 47% of Sears’ float was currently held by short-sellers, making it quite possible that today’s rally is being fueled by increased short covering.

Now what: I’d be taking today’s move higher with a grain of salt because short-covering rallies often have short-term price effects on a stock. After rebounding more than $20 off its 52-week lows, Sears is valued at roughly 90% of its book value. Then again, the company is forecasting losses at least through 2012 and has been losing ground to Home Depot (NYSE: HD), Wal-Mart (NYSE: WMT), and Lowe’s (NYSE: LOW). What many perceive as a value could actually be a value trap, and I’m inclined to stay far away from Sears.

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This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.