WASHINGTON, D.C. - In a sometimes combative setting before a District of Columbia U.S. Circuit Court of Appeals panel, parties argued March 25 over whether premium assistance is available under the Patient Protection and Affordable Care Act (ACA) for individuals who purchase insurance through the federal exchange because their state has not enacted an exchange (Jacqueline Halbig, et al. v. Kathleen Sebelius, et al., No. 14-5018, D.C. Cir.).