The US authorities have filed additional copyright infringement and fraud charges against Megaupload founder Kim Dotcom and other employees of the file-sharing site shut down last month.
The Justice Department said Friday that the new charges were added to the original indictment against Megaupload unsealed by a Virginia court on January 19.
The department said the superseding indictment also provides further evidence that Megaupload was engaged in massive piracy by facilitating downloads of copyrighted works.
While Megaupload claimed more than 180 million registered users, the site actually only had 66.6 million registered users, it said.
And of the total users, only 5.86 million had ever uploaded a single file to either Megaupload.com or Megavideo.com, the department said, demonstrating that more than 90 percent of Megaupload's users only used the site to download.
The indictment also said that Megaupload never took action against one user, identified only as "VV," who had been singled out as a repeat copyright infringer over a six-year period.
"VV" allegedly uploaded 16,950 files to Megavideo.com and Megaupload.com, which generated more than 34 million views, including copies of copyrighted movies such as "Ocean's Thirteen," "Ratatouille" and "Evan Almighty."
"Internal records reflect no deletions of any of VV's uploaded files," the Justice Department said.
The superseding indictment also listed additional assets subject to forfeiture including property, bank accounts, jet skis, jewelry and watches.
According to the Justice Department, five of the seven people charged have been arrested, including Dotcom, who is being held in New Zealand, and at least $50 million in assets has been seized.
Megaupload is the most high-profile target to date of a US campaign which has seen the seizure of hundreds of sites accused of offering pirated music or movies or counterfeit goods.
Explore further: Britain's UKIP issues online rules after gaffes