Two federal appellate panels on Tuesday issued conflicting rulings on the availability of subsidies for health insurance purchased on federally run exchanges and moved the next major battle over the Affordable Care Act closer to the U.S. Supreme Court.

A unanimous panel of the U.S. Court of Appeals for the Fourth Circuit, affirming a district court ruling, held that the Internal Revenue Service permissibly interpreted the law’s provision of subsidies to exchanges “established by the state” to include exchanges established by the federal government. However, a divided panel of the D.C. Circuit, reversing its district court, concluded otherwise.