Regis Resources Ltd's stock soared 5.08% during intraday trading on Monday, driven by the company's announcement of significant resource growth at its Tropicana joint venture in Western Australia.

The company reported that net of depletion, underground ore reserves have grown by 268% since 2018 at the joint venture. As of Dec. 31, 2025, mineral resources stood at 5.4 million ounces with ore reserves of 1.9 million ounces. Regis holds a 30% share of the Tropicana JV, representing 1.6 million ounces of gold.

The updated resource estimates, which show increased measured and indicated mineral resources, have boosted investor confidence in the company's asset base and future production potential, leading to the sharp price appreciation.