The shipping company allegedly conspired with two affiliated companies and two pharmacy groups to distribute the medications, which included narcotics, to people who had no valid prescriptions for the drugs.
Federal prosecutors said the allegedly illegal shipments netted FedEx $820 million in revenues.
"FedEx knew that it was delivering drugs to dealers and addicts," U.S. Attorney Melinda Haag's office said.
Should FedEx be found guilty of the charges, it could be fined twice the revenue in question.
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