Background
Tractor Supply Company (TSC), a national retailer operating stores throughout South Carolina, restructured its corporate form in 2001 to reduce state income taxes. The restructuring created two subsidiaries: Tractor Supply Company of Michigan, LLC (TSC Michigan) and Tractor Supply Company of Texas, LP (TSC Texas). After the restructuring, TSC Texas charged TSC and TSC Michigan a 9.7% markup on all inventory purchased from third-party sellers—based on a transfer pricing study by PricewaterhouseCoopers that had recommended a range of 3.9% to 12%. The restructuring was largely a paper transaction: the same employees continued performing inventory procurement functions from TSC’s corporate headquarters in Tennessee both before and after. The practical effect was dramatic: TSC shifted approximately $300 million in annual income to TSC Texas at the cost of only $13 million in salary savings. Because South Carolina requires separate-entity corporate reporting—each entity files its own return based solely on its own income, S.C. Code Ann. § 12-6-4910(2)—only TSC filed South Carolina taxes. TSC Texas’s income was effectively beyond the state’s reach.
The South Carolina Department of Revenue (the Department) audited TSC for calendar years 2014, 2015, and 2016. Finding that TSC’s inflated transfer price artificially depressed TSC’s taxable income and did not “fairly represent” TSC’s South Carolina business activity, the Department issued a determination requiring TSC to use combined unitary reporting (CUR)—a method that aggregates the income and apportionment factors of the entire corporate group. The assessment was $1,383,064 in additional taxes plus interest. TSC contested the assessment at the Administrative Law Court (ALC), which affirmed the Department after a full evidentiary hearing. TSC appealed to the Court of Appeals.
The Court’s Holding
A unanimous panel (Curtis, J., with Williams, C.J., and Thomas, J., concurring) affirmed the ALC on all three issues.
On distortion: The court rejected TSC’s argument that the ALC applied the wrong standard. TSC contended the analysis should focus solely on whether the sales factor fraction itself was operating incorrectly, not on whether the underlying income subject to apportionment was artificially depressed by transfer pricing. The court disagreed: adopting TSC’s “narrow interpretation” would allow any multistate taxpayer to inflate intercompany charges and render the standard apportionment formula meaningless as a measure of South Carolina business activity. The Department’s expert, Dr. David W. DeRamus, provided substantial evidence that the 9.7% markup was not arm’s length—no rational business would cede $300 million in income to save $13 million in salary costs for a function common to all retailers. The ALC credited Dr. DeRamus’s testimony over TSC’s expert, and the appellate court found that determination supported by substantial evidence.
On authorization for CUR: TSC argued that combined unitary reporting is not authorized by the apportionment statute, S.C. Code Ann. § 12-6-2320(A), because it “recalculates the tax base” rather than merely adjusting the apportionment fraction. The court rejected this argument as inconsistent with the South Carolina Supreme Court’s prior decision in Media General Communications, Inc. v. South Carolina Department of Revenue, 388 S.C. 138 (2010), which had already approved CUR as a permissible alternative method. The court expressly declined to follow a contrary Indiana decision, holding that South Carolina law as construed in Media General controls. The court also found substantial evidence that CUR was a reasonable and equitable method under Revenue Ruling 15-5’s three-factor test: it eliminated the distorting effect of the inflated transfer price, it did not expose TSC to double taxation, and it accurately reflected the economic reality of TSC’s South Carolina retail operations.
On the Administrative Procedures Act challenge: The court held that Revenue Ruling 15-5 (2015) is not an improperly promulgated regulation. The Ruling is interpretive guidance explaining how the Department evaluates CUR requests under authority already granted by § 12-6-2320 and Media General—not a binding norm creating new legal obligations. And TSC’s retroactive-surprise argument was undercut by its own decision to file a combined unitary return for tax year 2012, three years after Media General was decided.
Key Takeaways
- South Carolina’s alternative apportionment standard asks whether the taxpayer’s South Carolina business activity is fairly represented—not merely whether the sales factor fraction operates mathematically. Artificially inflated intercompany transfer pricing that shifts income to a non-filing affiliate can distort the apportionment result and justify the Department’s use of CUR, even if the arithmetic of the fraction is technically correct.
- Combined unitary reporting is an authorized alternative apportionment method in South Carolina under § 12-6-2320(A), as established by Media General. The Department need only show that CUR is reasonable and equitable and cures the identified distortion—it need not be the only possible remedy.
- SCDOR Revenue Ruling 15-5 is valid interpretive guidance, not a regulation subject to APA formalities. Taxpayers assessing CUR risk should treat it as the operative framework the Department applies when evaluating requests for alternative apportionment.
- A taxpayer that previously filed a combined unitary return for an earlier tax year after Media General was decided cannot credibly argue that CUR was an unexpected or unauthorized methodology for subsequent years.
- The General Assembly expanded the Department’s authority in this area effective March 11, 2024: amended § 12-6-2320(B) now expressly authorizes the Department to redetermine taxable income where intercompany transactions lack economic substance or are not at fair market value, including by requiring a combined unitary return.
Why It Matters
Tractor Supply confirms heightened audit risk for multistate corporations that use aggressive intercompany transfer pricing to shift income out of South Carolina. The Department’s authority to require CUR is backed by longstanding precedent (Media General) and a 2024 statutory amendment that codified and expanded that authority. Practitioners advising multistate retailers, manufacturers, or service companies with affiliated procurement, licensing, or management-service arrangements should audit their transfer pricing against the arm’s length standard developed in this case. A procurement markup that shifts hundreds of millions in income at the cost of only millions in actual salary savings will face serious scrutiny in a Department audit.
The decision also draws a sharp factual contrast with CarMax Auto Superstores West Coast, Inc. v. SCDOR, 411 S.C. 79 (2014), where the Department failed for lack of expert evidence establishing distortion. Tractor Supply illustrates what a successful CUR case looks like: credible expert testimony comparing the markup to arm’s length market norms, credited by the ALC and affirmed on substantial evidence review. South Carolina corporate taxpayers with interaffiliated structures should review both the pricing and the economic substance of those arrangements in light of this decision and the Department’s expanded 2024 tools.