Page:King v. Burwell.pdf/25

20 §18031]," §36B(b)(2); and then says that the term "coverage month" means any month in which the taxpayer has insurance through "an Exchange established by the State under [42 U. S. C. §18031]," §36B(c)(2)(A)(i).

We have held that Congress “does not alter the fundamental details of a regulatory scheme in vague terms or ancillary provisions." Whitman v. American Trucking Assns., Inc., 531 U. S. 457, 468 (2001). But in petitioners' view, Congress made the viability of the entire Affordable Care Act turn on the ultimate ancillary provision: a subsub-sub section of the Tax Code. We doubt that is what Congress meant to do. Had Congress meant to limit tax credits to State Exchanges, it likely would have done so in the definition of "applicable taxpayer" or in some other prominent manner. It would not have used such a winding path of connect-the-dots provisions about the amount of the credit.

Petitioners’ arguments about the plain meaning of Section 36B are strong. But while the meaning of the phrase “an Exchange established by the State under [42 U. S. C. §18031]” may seem plain “when viewed in isolation,” such a reading turns out to be “untenable in light of [the statute] as a whole.” Department of Revenue of Ore. v. ACF Industries, Inc., 510 U. S. 332, 343 (1994). In this instance, the context and structure of the Act compel us to depart from what would otherwise be the most natural reading of the pertinent statutory phrase.