California’s Throwback Rule - When determining the Taxpayer’s California Sales Factor, an out-of-state sale may be included in the Taxpayer’s numerator (treated as a California sale).
Every taxpayer (corporation, limited liability company, and limited partnership) that is organized in California, registered with the Secretary of State to do business in California, or "doing business" in California within the meaning of California Revenue and Taxation Code (R&TC) Section 23101 has a filing requirement in California (what form and the type of tax and fee depends on the entity type). The requirement to file a return and pay the taxes owed is imposed on each entity, including corporate taxpayers that are members of a combined reporting group, and multi-tiered pass-through business entities.
If a corporation has income from sources both within and outside California, it is required to allocate and apportion its income as provided in Chapter 17, Part II of the R&TC. For taxable years beginning on or after January 1, 2013, R&TC Section 25128.7 requires all business income of an apportioning trade or business, other than an apportioning trade or business under R&TC Section 25128(b), to apportion its business income to California using the single-sales factor formula.
When determining how much of the receipts from sales are assigned to the California sales factor numerator, California’s throwback rule (see R&TC Sections 25135 and 25122) needs to be considered. Under the California throwback rule, sales of tangible personal property are sourced to California if the property is shipped from a location in California and the purchaser is the U.S. government or the taxpayer is not taxable in the purchaser’s state. Under R&TC Section 25122, a taxpayer is taxable in another state if in that state it is subject to a net income tax, a franchise tax measured by net income, a franchise tax for the privilege of doing business, or a corporate stock tax.
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