California Revenue & Taxation Code
Cal. Rev. & Tax. Code § 13303
In a case where a decedent leaves property having a situs in this state, and leaves other property having a situs in another state, or other states, the portion of the maximum state death tax credit allowable against the federal estate tax on the total estate by the federal estate tax law which is attributable to the property having a situs in California shall be determined in the following manner:
# (a)
For the purpose of apportioning the maximum state death tax credit, the gross value of the property shall be that value finally determined for federal estate tax purposes.
# (b)
The maximum state death tax credit allowable shall be multiplied by the percentage which the gross value of property having a situs in California bears to the gross value of the entire estate subject to federal estate tax.
# (c)
The product determined pursuant to subdivision (b) shall be the portion of the maximum state death tax credit allowable which is attributable to property having a situs in California.
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