The U.S. Department of Agriculture implemented new rules in May that require packages of meat to be sold with labels that identify the country in which the animal was born, raised, and slaughtered. The rules also outlaw the mixing of cuts of meat from different countries in the same package. That pleased food-safety advocates, environmentalists, and some farmers.
But it angered large meat importers and producers and grocery chains. On Tuesday, some of those groups announced they were suing.