Attorneys for Amazon and Elon Musk’s SpaceX have argued in a federal appeals court that the National Labor Relations Board’s structure is unconstitutional.

Amazon and SpaceX are seeking to hamstring the National Labor Relations Board, asking a court to declare its processes for upholding labor law unconstitutional. But judges on a three-person panel appeared skeptical when the companies presented their arguments Monday.

SpaceX and Amazon are asking the Fifth Circuit Court of Appeals to find the National Labor Relations Board unconstitutional. The federal agency is tasked with enforcing workers' right to organize.

Elon Musk’s SpaceX Corp. today argued in a federal appeals court that the National Labor Relations Board is unconstitutional. In separate cases, attorneys for the two companies told a panel of judges at the Fifth Circuit Court of Appeals that the labor agency,