Apple Inc., Google LLC parent Alphabet Inc., Dell Technologies Inc., Microsoft Corp. and Tesla Inc. have sought to dismiss a lawsuit alleging the companies knowingly benefited from children mining cobalt in the Democratic Republic of Congo.

The firms said in an Aug. 25 court filing that the "expansive" legal theories put forward in the lawsuit are not supported by current law.

They also said that if the litigation were allowed to advance, it would "open the door" to a flurry of litigation against "any manufacturer, retailer, or even consumer of a product to be sued based on conduct by independent foreign actors anywhere in a global supply chain."

While the companies condemned the poor labor conditions outlined in the complaint, they said in the filing that through the mixing of cobalt from various sources, the metal they had purchased cannot be traced to any particular mine in the DRC and thus the plaintiffs' injuries are not "fairly traceable" to the companies' conduct.

Cobalt is a key ingredient in the manufacturing of lithium-ion batteries, which are used in a number of products including electric vehicles and consumer technology.

As part of a rising wave of criticism over human rights issues within tech and automobile supply chains, the lawsuit was filed in December 2019 on behalf of children and the families of children who were injured while working in cobalt mines in the DRC. The complaint sought damages for forced labor and an award for "unjust enrichment, negligent supervision and intentional infliction of emotional distress."

Alphabet and Dell also filed separate motions for their inclusion in the lawsuit to be dismissed, arguing Alphabet cannot be held liable for its subsidiaries' use of cobalt and the court lacks personal jurisdiction over Dell.

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