California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 18006
For purposes of determining a credit under Section 18001 (relating to residents) or Section 18002 (relating to nonresidents), both of the following apply:
# (a)
A member of a partnership is allowed to treat his, her, or its pro rata share of net income taxes paid to another state by the partnership as if those taxes had been paid directly by the partner.
# (b)
(1)A shareholder of a corporation that is an S corporation under Chapter 4.5 (commencing with Section 23800) of Part 11 is allowed to treat his or her pro rata share of net income taxes paid to another state by the S corporation as if those taxes had been paid by the shareholder.
(2)This subdivision applies only if either of the following requirements is met:
(A)The state imposing the tax does not allow corporations to elect to be treated as an S corporation.
(B)The state imposes a tax on S corporations and the corporation referred to in paragraph (1) has elected to be treated as an S corporation in the other state.
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