The Court of Appeal has overturned a High Court decision that ordered the disclosure of the documents that are the basis of the case against Dotcom.
The court said extradition hearings were not trials and the full protections and procedures for criminal trials did not apply.
US authorities want to extradite the German-born internet entrepreneur to stand trial on criminal charges alleging copyright piracy and racketeering.
Dotcom’s lawyer, Paul Davison, QC, said his legal team would seek to appeal to the Supreme Court.
The Supreme Court will need to give leave to appeal, as this would be the third appeal. The original ruling was in the District Court. The first appeal was to the High Court and the second appeal to the Court of Appeal.