Section 35 ILCS 5/305 - Allocation of Partnership Income by partnerships and partners other than residents(a) Allocation of partnership business income by partners other than residents. The respective shares of partners other than residents in so much of the business income of the partnership as is allocated or apportioned to this State in the possession of the partnership shall be taken into account by such partners pro rata in accordance with their respective distributive shares of such partnership income for the partnership's taxable year and allocated to this State. (b) Allocation of partnership nonbusiness income by partners other than residents. The respective shares of partners other than residents in the items of partnership income and deduction not taken into account in computing the business income of a partnership shall be taken into account by such partners pro rata in accordance with their respective distributive shares of such partnership income for the partnership's taxable year, and allocated as if such items had been paid, incurred or accrued directly to such partners in their separate capacities. (c) Allocation or apportionment of base income by partnership. Base income of a partnership shall be allocated or apportioned to this State pursuant to Article 3, in the same manner as it is allocated or apportioned for any other nonresident. (c-5) Taxable income of an investment partnership, as defined in Section 1501(a)(11.5) of this Act, that is distributable to a nonresident partner shall be treated as nonbusiness income and shall be allocated to the partner's state of residence (in the case of an individual) or commercial domicile (in the case of any other person). However, any income distributable to a nonresident partner shall be treated as business income and apportioned as if such income had been received directly by the partner if the partner has made an election under Section 1501(a)(1) of this Act to treat all income as business income or if such income is from investment activity: (1) that is directly or integrally related to any other business activity conducted in this State by the nonresident partner (or any member of that partner's unitary business group); (2) that serves an operational function to any other business activity of the nonresident partner (or any member of that partner's unitary business group) in this State; or(3) where assets of the investment partnership were acquired with working capital from a trade or business activity conducted in this State in which the nonresident partner (or any member of that partner's unitary business group) owns an interest. (d) Cross reference. For allocation of partnership income or deductions by residents, see Section 301(a).Amended by P.A. 093-0840, § 25-5, eff. 7/30/2004.