US Court Clears Path for Resolution Copper to Develop Oak Flat

The US Court of Appeals for the Ninth Circuit has rejected a request to revisit its earlier decision on the Oak Flat land transfer, clearing the way for Resolution Copper to proceed with its mining plans. On 29 September, the court denied a petition for rehearing en banc, effectively upholding its 13 March ruling that allows the transfer of approximately 2,400 acres of federal land in Arizona to Resolution Copper. The land exchange, completed on 16 March 2026, removes a significant legal barrier for the joint venture between Rio Tinto (55%) and BHP (45%).

Following the court's decision, Rio Tinto has initiated a US$500 million drilling program to explore portions of the copper deposit that were previously inaccessible. This step is crucial for establishing construction and production timelines. The Oak Flat deposit is estimated to contain over 40 billion pounds of copper, which could meet more than a quarter of US copper demand throughout its operational life.

While the legal hurdle has been cleared, permitting and processing economics remain potential risks for the project. The resolution of these issues will be critical in determining the future viability and success of the mining operation.