Employers who don’t include arbitration clauses in their employment contracts to prevent employees from filing class actions may want to start. The U.S. Court of Appeals for the Fifth Circuit has handed businesses a powerful weapon in disputes with workers in its decision in D.R. Horton v. National Labor Relations Board.

“It’s an enormous victory for employers because they now have an extremely valuable weapon available to them to fight class and collective action,” said Ron Chapman Jr., a Dallas shareholder in Ogletree, Deakins, Nash, Smoak & Stewart who represents D.R. Horton Inc.