(Reuters) – A federal appeals court on Tuesday refused to hold five major technology companies liable over their alleged support for the use of child labor in cobalt mining operations in the Democratic Republic of the Congo.

The U.S. Court of Appeals for the District of Columbia upheld a district judge’s dismissal of claims against Apple, Google parent Alphabet, Dell Technologies, Microsoft and Tesla.

Former cobalt miners had sued under the federal Trafficking Victims Protection Reauthorization Act, accusing the companies of participating in a “forced labor” venture with cobalt suppliers by purchasing the metal.

But the appeals court said buying cobalt through the global supply chain was not “participation in a venture” with the meaning of that law.

(Reporting by Jonathan Stempel in New York; Editing by Chizu Nomiyama)