In any taxable year in which the right referred to in subparagraph (2) of this paragraph is exercised, there is includible in the gross income of such taxpayer for such taxable year amounts retained or recovered by the taxpayer pursuant to the exercise of such right. If the provisions of paragraph (a) of § 1.163-4 (relating to deductions for original issue discount) apply to deposits made with respect to a certificate of deposit, time deposit, bonus plan or other deposit arrangement, the provisions of this paragraph shall not apply.
26 C.F.R. §1.591-1