WASHINGTON, March 26 (Reuters) - A U.S. judge on Thursday dismissed X Corp's antitrust lawsuit that accused the World Federation of Advertisers and a group of major companies including Mars, CVS Health ( CVS ) and Colgate-Palmolive ( CL ) of illegally boycotting billionaire entrepreneur Elon Musk's social media company.

U.S. District Judge Jane Boyle in the federal court in Dallas said Musk's X failed to show that it had suffered any harm under federal antitrust laws.