Key Takeaways Petrobras will return the ES-M-596 block in the Espirito Santo basin to the regulator ANP.Multiple wells drilled since 2018 have failed to show commercial viability for development.Petrobras still holds three other Espirito Santo blocks, including ES-M-669, under evaluation.Petrobras (PBR) , the Brazilian integrated oil and gas company, is set to return the ultra-deepwater block ES-M-596 located in the Espírito Santo basin to the National Agency of Petroleum, Natural Gas and Biofuels (“ANP”), ...