JPMorgan analyst Alexia Quadrani last night downgraded News Corp. to Underweight from Neutral and lowered her price target for the shares to $12 from $13. The analyst says that while the stock may appear attractively valued, she has little conviction in forward estimates. Quadrani, who points out she's reduced News Corp.'s estimates 12 times over the last three years, believes challenges will persist in the company's News and Information Services and Subscription Video Services divisions. Further, she sees weakness in new listings at REA and "further headwinds to growth continuing." The analyst looks for stabilization in her estimates or signs of strategic change as catalysts to reevaluate her rating.