Barnes & Noble said on Wednesday it was considering selling itself after receiving interest from multiple parties, including the company’s executive chairman and top shareholder, Leonard Riggio, the man who turned what had been a single Manhattan store into the largest U.S. bookstore chain.

The company, which has struggled with a lengthy streak of quarterly sales declines, has explored selling itself a number of times over the years, including an earlier buyout attempt by Riggio. Even though Barnes & Noble’s stock rose over 20% to 6.80 a share in after-hours trading after disclosing the review process, shares remain depressed by historical standards.

The company’s market value is around $400 million, down about 80% from its 2006 all-time high about $2 billion.

The retailer has struggled to compete with Amazon.com, which dominates the online sale of physical and digital books. In its most recent quarter, Barnes & Noble’s comparable sales fell 6.1% amid a strong consumer environment and rebounding sales of physical books. Despite a number of facelifts, the chain’s website has also failed to win favor with online book buyers; online sales fell 14% last quarter.

Adding to the pressure on the company, Barnes & Noble has had five CEOs in the last six years. Its most recent one, Demos Parneros, was fired abruptly in July after just more than a year in the job for violating company policies. (He has since suit the company for alleged wrongful termination.)

Barnes & Noble’s board has intermittently considered selling for years. In 2010, a year after a bruising battle with activist investor Ron Burkle, Barnes & Noble announced a sales process, and Riggio said at the time that he was considering forming a group to make the acquisition.

A year later, John Malone’s Liberty Media offered $1.02 billion but eventually invested $204 million instead. And in 2013, Riggio again said he was interested in buying Barnes & Noble’s bookstores (excluding the now spun off college bookstore business), but later dropped those plans.

More recently, the company has faced pressure from activist investors to sell itself. On Wednesday, Barnes & Noble also said it had adopted a short-term “poison pill” shareholder rights plan, after noticing “rapid material accumulations” of its stock by parties it couldn’t identify. The maneuver prevents anyone in the next year from building a stake in excess of 20% in the company without the board’s approval.