"Nowhere in the non-prosecution agreement does it state that because the defendants had settled wrongful death claims <t40>...<t$> that no additional restitution would be paid," the complaint says.
The families also say they were not party to discussions about the DOJ settlement and never agreed to give up their rights to "have those responsible for the death to be prosecuted for said crimes or criminal activities."
No hearing dates have been scheduled.
Upper Big Branch was the worst U.S. coal mining disaster in 40 years.
Four investigations found that worn and broken cutting equipment created a spark that ignited accumulations of coal dust and methane gas. Broken and clogged water sprayers allowed what should have been a minor flare-up to become an inferno.
The federal Mine Safety and Health Administration said the root cause was Massey's "systematic, intentional and aggressive efforts" to conceal life-threatening problems. Managers even maintained two sets of pre-shift inspection books -- an accurate one for themselves, and a sanitized one for regulators.
Former superintendent Gary May and security chief Hughie Elbert Stover are behind bars for their actions at the mine.
A former president of another Massey subsidiary, meanwhile, is awaiting sentencing for conspiracy.
David Hughart is cooperating with prosecutors and has testified that other Massey operations gave miners underground warnings that inspectors were onsite. He's set to appear before Berger on Sept. 10.