He has not been able to access the assets because of a foreign restraining order made at the time of his high-profile arrest in Coatesville in January 2012.
The order expired in April and the High Court turned down a police application to extend it.
That decision was appealed, and today's decision quashes it and extends the restraining order until April next year.
The orders were originally made using a criminal process that would mean Dotcom's assets wouldn't be forfeited until there was a conviction in the case in the US.
Authorities then decided to use a different, civil process that would mean the assets would be within reach before the completion of Dotcom and his co-accused Bram van der Kolk's extradition process.
Dotcom's lawyer Robert Gapes argued that change of grounds was unfair and should not be allowed under the law.
However, today's decision found that it was appropriate to extend the order and the switch to civil forfeiture was not significant.
"The evidence before the Court is that forfeiture proceedings of a kind contemplated by the US restraining orders can be completed before April 2015," stated the judgment, which was delivered by Justice Mark O'Regan, president, Justice John Wild and Justice Christine French.
Dotcom has been travelling the country in his role as founder of the Internet Party.