Comcast is the largest cable company and home Internet service provider in the United States. Matt Rourke/AP hide caption

itoggle caption Matt Rourke/AP

An NBC store is seen through a window reflecting Rockefeller Center in New York City. Comcast, the nation's largest cable company, has owned 51 percent of NBCUniversal since 2011. Chris Hondros/Getty Images hide caption

itoggle caption Chris Hondros/Getty Images