Maori organisations have lost their bid to stop the government's partial privatisation of state-owned Mighty River Power.
The Maori Council and Waikato River and Dams Claims Trust had challenged the government's decision to sell MRP shares without first ensuring there was a mechanism to recognise Maori water rights.
They said the changes in ownership would be in breach of the principles of the Treaty of Waitangi because they would prejudice Maori claims to water.
But in a decision delivered in the Supreme Court in Wellington, Chief Justice Dame Sian Elias said selling a stake in MRP, the first of four energy companies due for partial sale, would not impair the Crown's ability to remedy Treaty breaches.
The parties had gone directly to the Supreme Court from the High Court, where Justice Ronald Young ruled a decision by parliament can't be reviewed by the courts.
The Supreme Court overturned Justice Young on that point, saying the proposed sale is reviewable for consistency with the principles of the Treaty.
But it found government consultation on water rights after a Waitangi Tribunal recommendation was adequate, and that the partial sale of the assets "will not impair to a material extent the Crown's ability to remedy any Treaty breach in respect of Maori interests in water".
The decision clears the way for government plans to sell 49 per cent of MRP between March and June.
It is the first asset sale in a programme the government hopes will raise between $5 billion and $7 billion, though that number is looking harder to predict given the difficulties of one company marked for sale, Solid Energy.