Brazil’s 12% crude oil export tax, imposed via provisional measure in March 2026 to offset fuel subsidies amid Middle East supply disruptions, faces sustained constitutional challenges from producers including ABEP and majors such as Shell, Equinor, and TotalEnergies. Courts have alternated between granting and reversing injunctions on grounds of tax anteriority, separation of powers, and the levy’s revenue-raising character after the original measure lapsed and Gecex resolutions extended it. Petrobras reported billions in payments, while lower-court volatility and pending appeals to the STF create uncertainty over producer margins, export volumes, and capital allocation. Key near-term catalysts include Gecex extension decisions, further appellate rulings, and any STF scheduling on the underlying legality.