PRIO: Production of the Fourth WAHOO Well

June 16, 2026 – PRIO S.A. (the “Company” or “PRIO”) (B3: PRIO3), in compliance with best corporate governance practices, hereby informs its shareholders and the market in general that it has opened the fourth producing well at the Wahoo Field (“Field”), stabilizing its production at 10,000 barrels of oil per day.

As a result, PRIO has completed the startup of all producing wells planned for the Wahoo development project and, as previously disclosed, the Company will limit the Field’s total production to 40,000 barrels of oil per day.