Claim for a credit or refund of an overpayment of any tax imposed by this chapter shall be filed by the taxpayer with the Commissioner not later than 3 years from the last date prescribed for filing the return (including the time permitted in any agreements for the extension of time) or 2 years from the time the tax was paid, whichever of such periods is later, or if no return was filed by the taxpayer, not later than 2 years from the time the tax was paid.
5 Del. C. § 1112