share: digg facebook twitter The bid of $17 a share in cash from the conglomerate chaired by billionaire media mogul John Malone sent Barnes & Noble's stock surging more than 24 percent in extended trading after the company announced the potential deal. The companies haven't yet signed an agreement, and the deal is still subject to closing conditions, including one that founding chairman Leonard Riggio keep a stake in the company and remain in a management position, Barnes & Noble said. Liberty Media operates three publicly traded companies — Liberty Interactive Inc., Liberty Starz Group and Liberty Capital Group — through which it runs home-shopping network QVC, movie channel operator Starz LLC and holds stakes in numerous other online, media and communications companies. Traditional book sellers have been facing increasing competition from online retailers and discounters such as Amazon.com Inc.