A US jury on Wednesday found that entertainment giant Live Nation wielded monopoly power at its Ticketmaster business, violating federal and state antitrust laws, according to California’s attorney general.A verdict that could have profound repercussions in the concert world came after four days of deliberations, and remedies could include breaking up Live Nation and Ticketmaster.The jury found Live Nation and Ticketmaster liable for anticompetitive conduct that harmed the music industry and...