§ 6407

(a) A Headquarters Management Corporation shall be credited with the amount of any income tax paid under this chapter on income upon which income tax (or tax computed upon or by reference to income) was also paid with respect to the taxable year to any other state of the United States or the District of Columbia. (b) The credit provided by this section shall be allowed only if the taxpayer establishes to the satisfaction of the Secretary: (1) The total amount of income derived from sources without this State, (2) The amount of income derived from each state, (3) The amount and nature of the tax paid to each state, and (4) All other information necessary for the verification and computation of such credit.74 Del. Laws, c. 256, § 1;