In December 2024, we shared a victory from the Fifth Circuit Court of Appeals, which upheld a $14.25 million civil penalty against ExxonMobil Corporation and its affiliates for violating its Clean Air Act permit. Exxon spewed hazardous air pollution into communities surrounding its Baytown, Texas refinery and petrochemical complex on thousands of occasions. This remains the largest financial penalty ever imposed by a court in a Clean Air Act citizen suit and is a result of years of litigation by Sierra Club and partners—we originally sued Exxon in 2010.
After this incredible 2024 victory, Exxon continued to fight, attempting to appeal this decision to the U.S. Supreme Court. On June 30, 2025, the Supreme Court declined to take up this case, ending Exxon’s efforts to challenge this ruling. Exxon lost four previous appeals at the Fifth Circuit Court of Appeals prior to this Supreme Court rejection.
Neil Carman, Sierra Club’s Lone Star Chapter Clean Air Director said:
“We knew Exxon would fight this all the way to the Supreme Court, but we matched their persistence so they could not escape responsibility for their years of illegal air pollution.”