Tribune Broadcasting Company, LLC was an American media company which operated as a subsidiary of Tribune Media, a media conglomerate based in Chicago, Illinois. The group owned and operated television and radio stations throughout the United States, as well as full- or partial-ownership of cable television and national digital subchannel networks. History Tribune's broadcasting unit originated with the June 1924 purchase of Chicago, Illinois radio station WDAP by the Chicago Tribune. The new owners changed the station's call letters to WGN, to match the Tribunes slogan, "World's Greatest Newspaper" first used by Tribune in a February 1909 feature commemorating the 100th anniversary of the birth of Abraham Lincoln and then served as the newspaper's motto from August 29, 1911, until December 31, 1976. On September 13, 1946, the Federal Communications Commission (FCC) granted Tribune license to operate a television station on channel 9 in Chicago and then signed-on a television station in Chicago, WGN-TV on April 5, 1948, initially as a dual affiliate of CBS and the DuMont Television Network. Two months later, the Tribunes then-sibling newspaper in New York City, the Daily News, established its own television station, independent WPIX. WGN-TV became an independent outlet by 1956, and would eventually morph into a pioneering national superstation on November 9, 1978, as its signal was linked to cable and satellite customers across America. After McCormick succumbed from pneumonia-related complications on April 1, 1955, ownership of WGN-TV-AM, the Chicago Tribune and the News Syndicate Company properties would transfer to the McCormick-Patterson Trust, assigned to the Robert R. McCormick Tribune Foundation in the names of the non-familial heirs of McCormick (whose two marriages never produced any children) and familial heirs of Patterson. (The trust was dissolved in January 1975, with a majority of the trust's former beneficiaries, including descendants of the McCormick and Patterson families, owning stock in the restructured Tribune Company entity – which assumed oversight of all properties previously overseen by the trust – afterward.) In subsequent years, the Tribune Company gradually expanded its broadcasting unit, of which WGN-TV-AM served as its flagship stations, a tie forged in January 1966, when the subsidiary (sans the WPIX television and radio stations, which continued to be controlled by the Tribune-managed News Syndicate Co. before being fully integrated into the company's main station group following its 1991 sale of the Daily News) was renamed the WGN Continental Broadcasting Company. The group became known