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What: Shares of Barnes & Noble (NYSE:BKS) were getting torn apart once again today, falling as much as 17% after posting another underwhelming earnings report and revealing that founder Leonard Riggio has backed away from an offer to buy the company's retail stores.

So what: The bookseller said it ended its first quarter with an adjusted net loss of $0.86 per share, down from $0.76 a year ago, and worse than the analyst estimate at $0.81. Revenue dropped 9% to $1.33 billion, though that was slightly ahead of the consensus at $1.32 billion. Meanwhile, same-store sales tumbled 9.1%, and sales from the Nook dropped 39% to $143 million, both foreboding signs as same-store sales are often seen as the best indicator of a retailer's prospects, and the Nook was once believed to be Barnes & Noble's saving grace -- though the company announced last month that it would discontinue the Nook Color tablet due to poor performance.

Now what: Adding insult to injury, former chairman Riggio stepped back from potential plans to buy the company's retail stores, saying, "While I reserve the right to pursue an offer in the future, I believe it is in the company's best interests to focus on the business at hand." The statement was a blow to investors who were hoping Riggio would come to the ailing retailer's rescue, and the CEO post remaining vacant after William Lynch stepped down last month is yet another reason to bet against the stock. With Nook sales fading and the founder's buyout now merely a fantasy, it's hard to see what, if anything, will stop Barnes & Noble's bleeding.