The company says its millions of users stored their own data, including family photos and personal documents.
Megaupload hires outside companies to store the data, for a fee. But Megaupload attorney Ira Rothken said Sunday that the government has frozen its money.
A letter filed in the case Friday by the U.S. Attorney's Office for the Eastern District of Virginia said storage companies Carpathia Hosting Inc. and Cogent Communications Group Inc. may begin deleting data Thursday.