61 Pa. Code § 9.12
(c) To administer the CNI Tax in a constitutional manner, an additional deduction from the CNI Tax base for foreign dividends is required. See—for example—Commonwealth v. Curtis Publishing Co., 363 Pa. 299, 69 A.2d 410 (1949). Until the General Assembly amends the affected provision of the CNI statute, the Department finds that by allowing a deduction for foreign dividends in the following manner, discrimination is remedied and the original intent of the General Assembly to tax at least a portion of Federally-taxable dividends is achieved.
(1) The Department will allow foreign dividends reported on lines 13 and 14 of the Federal return Schedule C an additional deduction equal to one of the following: