The Motion Pictures Association of America (MPAA) has revealed that six of its major movie studios will be looking to file a lawsuit against Megaupload and its "key operators."
Prior to its 2012 shut down, Megaupload was one of the largest file-sharing websites in the world with 150 million registered users.
The website cost copyright holders, according to US regulators, more than £320 million in lost revenue.
Among the big studios looking for reparation are Twentieth Century Fox, Disney, Paramount, Universal and Warner Bros.
The MPAA has alleged that despite founder Kim Dotcom's assertions that the website was a storage service, Megaupload paid users to upload popular content.
"Megaupload was built on an incentive system that rewarded users for uploading the most popular content to the site, which was almost always stolen movies, TV shows and other commercial entertainment content," Steve Fabrizio, general counsel for the MPAA, said in a statement (PDF).
Dotcom has come back at these allegations, claiming over Twitter that files any bigger than 100MB did not earn rewards:
"Hollywood claims that we were paying users to upload pirated movies. Stupid"
Following the closure of Megaupload, Dotcom went on the found another storage-based service, Mega, which gained 1 million users in just 24 hours.
He is currently fighting extradition from New Zealand to the United States where he will be held liable for the copyright charges levelled against him and Megaupload.