Exxon Mobil Corp. & Affiliated Cos. v. Commissioner

JOSÉ A. CABRANES, Circuit Judge:

Under section 6621 of the Internal Revenue Code (“I.R.C.”), interest is calculated at a higher rate for corporate tax underpayments than it is for corporate tax over-payments. 2 In principle, therefore, a corporate taxpayer could owe the Treasury underpayment interest even if the amount by which the taxpayer had underpaid its taxes in one tax year (or set of tax years) was entirely offset by the amount by which it had overpaid in another tax year (or set of tax years). 3 To remedy this apparent inequity, Congress amended section 6621 in 1998 to include a…