Cosa Reports Anomalous Radioactivity in Multiple Drill Holes at the Murphy Lake North Joint Venture with Denison Mines

Vancouver, British Columbia, April 13, 2026 – Cosa Resources Corp. (TSX-V: COSA) (OTCQB: COSAF) (FSE: SSKU) (“Cosa” or the “Company”) is pleased to report the intersection of anomalous radioactivity in multiple drill holes and completion of the winter 2026 drilling program at the Company’s Murphy Lake North Project (“MLN” or the “Project”). MLN is a joint venture (the “Joint Venture”) between Cosa and Denison Mines Corp. (“Denison”) (TSX: DML) (NYSE American: DNN) and is located 3 kilometres east of IsoEnergy’s Hurricane deposit in the eastern Athabasca Basin, Saskatchewan (Figure 1). Cosa is the operator and holds a 70% interest with Denison holding a 30% interest.