McDonald’s and Burger King fought it out in court.

The Battle of the Burgers between the two American fast-food giants ended in a London High Court with each side claiming it had singed the other. After five days of testimony, Judge John Whitford granted McDonald’s an injunction barring Burger King from using an advertisement that knocked McDonald’s best-selling burger, the Big Mac. But the judge rejected McDonald’s claim that Burger King, home of the Whopper, had maliciously implied that McDonald’s hamburgers were less than 100% beef. McDonald’s sued its rival for alleged trade libel over a three-month 1983 ad campaign in the London subway system featuring ads picturing a huge hamburger and the slogan, “It’s Not Just Big, Mac.” In smaller print, the ad described the Whopper and said: “Unlike some burgers, it’s 100% pure beef.”