(a) Questions have arisen as to the requirements of 9904.403, Cost Accounting Standard, Allocation of Home Office Expenses to Segments, for the purpose of allocating State and local income taxes and franchise taxes based on income (hereinafter collectively referred to as income taxes) from a home office of an organization to its segments.

(b) By means of an illustrative allocation base in 9904.403-60, the Standard provides that income taxes are to be allocated by “any base or method which results in an allocation that equals or approximates a segment's proportionate share of the tax imposed by the jurisdiction in which the segment does business, as measured by the same factors used to determine taxable income for that jurisdiction.” This provision contains two essential criteria for the allocation of income taxes from a home office to segments. First, the taxes of any particular jurisdiction are to be allocated only to those segments that do business in the taxing jurisdiction. Second, where there is more than one segment in a taxing jurisdiction, the taxes are to be allocated among those segments on the basis of “the same factors used to determine the taxable income for that jurisdiction.” The questions that have arisen relate primarily to whether segment book income or loss is a “factor” for this purpose.

(c) Most States tax a fraction of total organization income, rather than the book income of segments that do business within the State. The fraction is calculated pursuant to a formula prescribed by State statute. In these situations the book income or loss of individual segments is not a factor used to determine taxable income for that jurisdiction. Accordingly, in States that tax a fraction of total organization income, rather than the book income of segments within the State, such book income is irrelevant for tax allocation purposes. Therefore, segment book income is to be used as a factor in allocating income tax expense from a home office to segments only where this amount is expressly used by the taxing jurisdiction in computing the income tax.