Kim Dotcom has been granted leave to appeal his case against the Crown in the Supreme Court.
The Megaupload founder's legal team applied in March to be heard in the country's highest court after a decision about disclosure made in the Court of Appeal went against him.
Dotcom's lawyers want to be able to view the documents that make up the basis of the US Government's case against him.
US authorities are seeking to extradite the German-born internet entrepreneur to stand trial on criminal charges alleging copyright piracy and racketeering.
The Crown, on behalf of the US, argue he should not be allowed to see the documents..
Judges in the District Court and High Court ruled in favour of disclosure, but the Court of Appeal ruling made in March said extradition hearings were not trials and the full protections and procedures for criminal trials did not apply.
So far, US authorities have filed a 109-page record of the case against Dotcom, the contents of which are suppressed.
Dotcom denies his MegaUpload internet storage facility encouraged copyright breaches and wants to use the extradition hearing to challenge the assumptions made against him.
A date is yet to be set for the Supreme Court hearing.
Dotcom's extradition hearing is due to get under way in August, however it looks likely to be delayed again, as several strands of the case continued to be appealed.
The 39-year-old, a New Zealand resident, was arrested in a dramatic raid on his rented Coatesville mansion, north of Auckland, on January 20 last year.
Computers and assets were seized as New Zealand police co-operated with US authorities.