Megaupload founder Kim Dotcom is suing Hong Kong to unfreeze his company's assets in the country.
The plea for the defunct file storage site means the High Court of Hong Kong has ordered the Department of Justice to respond by June 4.
In its application, Megaupload has called for Hong Kong's Department of Justice to toss the US-driven restraint order that led to its headquarters there being shutdown in January 2012 and the company's assets frozen.
Dotcom hopes success would mean the file sharing site can restart its servers, allowing users to retrieve their files.
The US is still to initiate criminal charges against the file-sharing site.
Megaupload global litigation counsel Ira Rothken, cited by torretfreak.com, said the US has yet to serve Megaupload or initiate substantive criminal proceedings against it, trapping Megaupload in a state of criminal limbo.
"During that time, the restraint order has prevented Megaupload from conducting business or paying bandwidth expenses needed to return cloud storage data to users," Rothken said.
"Needless to say, Megaupload and its cloud storage users have been severely prejudiced by the US Department of Justice's conduct."
The plea from Dotcom came after a New Zealand court ordered the release of the company's assets earlier this month, which included a car, cash and property seized during a crackdown in January 2012.
During the crackdown, New Zealand police seized about 15 luxury vehicles including a pink 1959 Cadillac and other assets.
Following closure of the file-sharing site, Dotcom has launched another file storage site called Mega and started his own political party in New Zealand.
The Megaupload website has been accused of causing revenue losses of more than $500m to copyright holders before it was shut down in January 2012.
The US is seeking extradition of Dotcom on charges of racketeering, money laundering and copyright infringement.
Extradition has also been sought of his associates including Finn Batato, Mathias Ortmann and Bram van der Kolk.