The Supreme Court will decide whether Kim Dotcom's lawyers receive all the FBI investigation files before the internet mogul's extradition hearing.
In a judgement released today, the Supreme Court has granted leave to appeal.
That appeal comes after the Court of Appeal reversed a decision to allow Dotcom the documents.
Dotcom, Finn Batato, Mathias Ortmann and Bram van der Kolk are defending charges of mass copyright infringement, online piracy, and money laundering.
An Auckland District Court judge ruled last May that the FBI should hand over all its evidence relating to the extradition bid.