1624 ET - Brazilian oil-and-gas companies Brava Energy and Prio, both of which recently reported robust second-quarter profits, illustrate how Brazil's increasingly decentralized oil-and-gas sector enables smaller producers to thrive independent of state-controlled Petrobras, often by operating assets once owned by the energy giant, says Oscar Decotelli, chairman of Rio de Janeiro-based DXA Group, a private-market technology provider and investment firm. "I do not need Petrobras' balance sheet or its politics to make money in the Brazilian oil sector. I need a mature field [and] a disciplined operator," Decotelli says. Less reliance on Petrobras reduces perceived political risks for other Brazilian oil-and-gas producers and helps them attract foreign investors, he adds. Asset manager BlackRock in New York owned a roughly 7.5% stake in Prio at the end of June.