Users of Megaupload - including the law-abiding - are set to lose all their data as early as this week.
The popular file-sharing site - one of the 100 most-visited websites on the internet - was closed down nearly two weeks ago by the Department of Justice. The DoJ claimed it had generated more than $175 million in criminal proceeds for its owners through violation of copyright.
According to reports, federal prosecutors have said that data could start being deleted on Thursday, according to several reports. Because Megaupload's assets have been frozen, it's no longer able to pay Carpathia Hosting and Cogent Communications, the companies that store data on its behalf.
And with the Department of Justice saying it's copied all the data it needs from Megaupload's servers, it no longer has a right to access the servers on which the data is held.
The move would affect as many as 50 million Megaupload users, many of whom have been using it to store personal documents and photos, or even backing up business information, and who have never illegally copied or shared copyrighted material.
However, the Pirate Party, headed by its Catalonian unit, is fighting back.
"By closing the service, they have impeded the access to millions of archives of both private individuals and organisations, potentially causing huge personal, economic and image damages to a vast number of people," says the group.
"In addition, the Pirate Party understands they may have violated Articles 197 and 198 of the Spanish Penal Code by misappropiating personal data."
The group is asking affected users to get in touch, and says it plans to launch legal challenges to the takedown in as many countries as possible.
UPDATE: Carpathia points out that it has no access to the user content held on the megaupload servers, and therefore can't do anything to return it.
"The reference to the Feb. 2, 2012 date in the Department of Justice letter for the deletion of content is not based on any information provided by Carpathia to the US Government," it adds - although there's no word on whether or when data will be deleted.
It's asking Megaupload customers not to get in touch.