Hollywood studios have signalled a global intent to sue those who contributed to putting copyrighted movies on Kim Dotcom's Megaupload website.
The threat has come in a legal letter from the studios industry body, the Motion Picture Association of America, which said it wanted the file-sharing site's membership records preserved.
It is the latest stage in the courtroom battle following the January 20 raids against Dotcom and his Megaupload business.
The US Department of Justice organised raids around the world after getting arrest warrants for Dotcom and colleagues on charges of criminal copyright violation over movies and music on his site.
The data sits on servers owned by US-based company Carpathia Hosting, which has been warned by the Hollywood power lobby, the Motion Picture Association, to protect the data.
A letter from the MPA, on the court file in United States District Court in East Virginia, stated "the studios hold the rights to some of the most famous and valuable entertainment properties in the world".
It claimed copyright on the property had been "repeatedly and wilfully infringed through Megaupload on a massive scale".
Lawyer Steven Fabrizio said the Hollywood studios intended to sue Megaupload and "potentially ... those who have knowingly and materially" contributed to copyright infringement.
Fabrizio said Carpathia must maintain all Megaupload information - including movies, music and detailed membership records.
He said the Hollywood studios wanted access to details of "the Megaupload users who uploaded or dowloaded those files".
Part of Megaupload's earlier model involved payments to those who uploaded material. It was a practice which had been dropped by the time of the raid.
Fabrizio said the MPA wanted details of all payments made to those who had uploaded content.
The letter emerged in documents submitted by Carpathia which sought an order about what to do with the data.
It prompted MPAA vice president Howard Gantman to reassure individual members they would not be targeted in law suits.
He told Wired: "The reason we did that filing [was] that there is a possibility that litigation might be pursued against Megaupload or various intermediaries involved in Megaupload's operation. We're not talking about individual users." Wired said Gantman would not the "intermediaries" that might be sued.
Carpathia controller Theresa Pittinger said the 1103 computer servers previously rented by Megaupload held 28 petabytes of data - the equivalent to 330 years of HDTV or about half the words ever written, in any language.
With Megaupload's assets seized, it was costing $9000 a day just for air conditioning in the server rooms. Carpathia wanted to move them to a cheaper room costing $37,000 a month but it would also cost to shift them.
Along with the Hollywood studio interest, the company was also facing requests from Megaupload's lawyers for access to fight its court battles.
Carpathia sought permission from the court to either delete the data or to get those interested in the data to pay for its upkeep.
Meanwhile, the New Zealand police is about to decide whether it is going to back the United States prosecution with taxpayer money.
Dotcom's lawyers went to the court wanting the Crown to nominate the government department which would be the focus of a law suit if if the extradition failed and the US case collapsed.
The High Court directed a government department step forward as the likely respondent - and also signalled Dotcom was likely to have all his assets released if no one volunteered.
The Crown Law Office spent a month in meetings working out which department would be liable. The Herald on Sunday has been told Marshall will shortly nominate the police as the department which would represent the Crown if it weas sued.
A legal expert said the possibility of a law suit against the Crown would only come if all legal moves to extradite Dotcom failed, or the US case was lost. There was also an element of protection for law enforcement authorities carrying out their duties in good faith.