MGM has quietly bought back the 30 percent of United Artists that it didn't own from Tom Cruise and his producing partner Paula Wagner and now plan to revive the banner, published reports said Thursday. In 2006, MGM formed a joint venture with Cruise and Wagner to create a new specialty unit. But they produced only two films, Lions for Lambs, which earned only $15 million domestically in 2007 despite the fact that it starred Robert Redford, Meryl Streep, Andrew Garfield and Cruise, and Valkyrie , which earned $83 million domestically a year later . In 2008, Wagner stepped down as CEO and was not replaced. Also on Thursday, MGM said that it had named veteran television executive Peter Ligouri to its board of directors.