This study provides a comprehensive analysis of the United States federal Research and Development tax credit and Tennessee state tax incentives, applied specifically to the industrial ecosystem of Clarksville, Tennessee. By analyzing five prominent local industries, this document outlines how businesses leverage historical regional advantages alongside complex federal and state tax doctrines to monetize their technical innovations. [cite: 1]

Clarksville Industry Case Studies and Economic Development Analysis

The economic architecture of Clarksville, located in Montgomery County, Tennessee, has undergone a radical transformation over the past century. Originally established in 1784 as a transportation and inspection hub for the dark-fired tobacco trade along the confluence of the Cumberland and Red rivers, the city has strategically repositioned itself as a premier destination for high-value manufacturing, aeronautics, and advanced technology. This transition is anchored by structural geographic and demographic advantages: proximity to the “Auto Alley” corridor of Interstate 24, abundant energy supplied by the Tennessee Valley Authority (TVA), a highly disciplined veteran workforce transitioning from the adjacent Fort Campbell military installation, and a customized STEM talent pipeline developed in partnership with Austin Peay State University (APSU). [cite: 1]

The following five case studies examine specific industries deeply rooted in Clarksville’s history, detailing the rationale behind their regional development and illustrating how they navigate the rigorous requirements of both the United States federal and Tennessee state tax codes to claim Research and Development (R&D) incentives. [cite: 1]

Case Study 1: Advanced Metallurgy and Metal Casting

Historical Context and Regional Development Clarksville’s industrial foundation was built on metallurgy. The region’s proximity to raw timber for charcoal and surface iron ore deposits along the Western Highland Rim made it an ideal location for 19th-century foundries. The Clarksville Foundry, established in 1847 by H.P. Dorris near the original town spring, is one of the oldest continuously operating foundries in the United States. During the American Civil War, operating under the name Whitfield, Bradley & Co., the site served as a vital munitions factory producing rifled cannons and solid shot for the Confederacy until the city was captured by Union forces in 1862. Following the war, the industry modernized rapidly. By 1912, under the leadership of Thomas B. Foust, the foundry introduced mass-produced municipal castings, and in 1943, it adapted to the revolutionary invention of ductile iron, which offered unprecedented flexibility and tensile strength. Today, modern foundries in the Clarksville area leverage advanced technologies, including high-frequency coreless electric induction furnaces and spectrography, to produce highly customized architectural, industrial, and defense-related castings. [cite: 1]

Application of United States Federal R&D Tax Credit Laws Under Internal Revenue Code (IRC) Section 41, modern metallurgy relies heavily on the hard sciences of materials engineering and thermodynamics, satisfying the requirement that research be “technological in nature”. When a Clarksville foundry is contracted to cast a complex, geometric component utilizing a novel, high-strength ductile iron alloy, the engineering team inevitably encounters technical uncertainty regarding optimal cooling rates, gating system designs, and exact magnesium treatment ratios necessary to prevent structural porosity or metallurgical failure. [cite: 1]

To eliminate this uncertainty, the engineers engage in a systematic process of experimentation. They utilize Computer-Aided Design (CAD) flow simulations to model the molten iron’s behavior and subsequently execute iterative, physical test pours on the foundry floor, measuring the outcomes against strict tensile and yield strength specifications. The wages paid to the metallurgical engineers conducting these simulations, as well as the cost of the raw materials (sand, iron, alloying agents) consumed and destroyed during the failed test castings, constitute Qualified Research Expenses (QREs) under the federal framework. [cite: 1]

Application of Tennessee State Tax Incentives While Tennessee does not offer a direct payroll tax credit for these engineering wages, the state heavily incentivizes the capital equipment required to conduct this metallurgical research. To test the experimental ductile iron alloys, the foundry must purchase advanced diagnostic equipment, such as Brinell hardness testing machines, optical emission spectrophotometers, and thermal imaging cameras. By filing an Application for Research and Development Machinery Sales and Use Tax Exemption (Form RV-F1325101) with the Tennessee Department of Revenue, the foundry can demonstrate that the ultimate goal of these equipment purchases is “advancing knowledge or technology in a technical field” or the “design and development of prototypes”. Upon approval, the foundry can acquire this sophisticated testing apparatus entirely exempt from Tennessee’s state and local sales and use tax, representing a capital expenditure reduction of nearly 10%. Furthermore, under Tennessee Code Annotated (T.C.A.) § 67-4-2009, this R&D machinery qualifies for a 1% Franchise and Excise (F&E) tax credit, providing a direct offset against the foundry’s corporate tax liability. [cite: 1]

Case Study 2: Commercial HVAC and Climate Control Manufacturing

Historical Context and Regional Development Following the conclusion of World War II, the United States experienced a massive commercial construction boom that drove unprecedented demand for centralized climate control systems. Trane Technologies, originally founded as a family plumbing business in Wisconsin in 1885 and incorporated in 1913, capitalized on this boom by expanding its air conditioning lines. In the 1950s, Trane sought a strategic location to manufacture heavy, self-contained commercial packaged units that could be delivered ready for installation. Clarksville was selected due to its geographic centrality, offering highly efficient logistical access to the expanding markets of the American South and Midwest via rail and interstate networks. Today, the Trane facility in Clarksville is a cornerstone of the local economy, employing over 2,000 workers and operating in partnership with a robust, highly skilled unionized labor force represented by the International Association of Machinists and Aerospace Workers (IAM) Local 1296. [cite: 1]

Application of United States Federal R&D Tax Credit Laws The development of commercial Heating, Ventilation, and Air Conditioning (HVAC) systems is an incredibly complex engineering endeavor encompassing fluid dynamics, heat transfer, and acoustics. In an era of stringent environmental regulations, if the Clarksville facility initiates a project to design a proprietary variable-speed reciprocating compressor aimed at drastically increasing Seasonal Energy Efficiency Ratio (SEER) ratings while simultaneously reducing decibel output, they are engaging in qualified research. [cite: 1]

The “Business Component” test is satisfied as the new compressor is a product held for sale. The technical uncertainty lies in how the new refrigerant gases will interact with the experimental compressor valve designs under extreme thermal loads. The process of experimentation involves building multiple physical prototypes and subjecting them to rigorous evaluation within extreme temperature stress-test chambers. The direct engineering labor, the costs of third-party contract research utilized for specialized acoustic modeling (eligible at 65%), and the materials utilized to construct the functional prototypes are all deductible QREs under IRC Section 41. [cite: 1]

Application of Tennessee State Tax Incentives The HVAC manufacturing sector benefits significantly from the Tennessee Works Tax Act of 2023. Historically, the Tennessee Franchise tax was calculated based on the greater of a company’s net worth or the book value of its real and tangible property within the state. For a massive, capital-intensive manufacturing plant like Trane’s, this property measure resulted in a substantial tax burden. However, the recent legislative overhaul is phasing in a single sales factor apportionment formula, fully effective for tax years ending on or after December 31, 2025. This means that the tax liability for the Clarksville facility will be heavily weighted by sales made within Tennessee, rather than penalizing the company for housing massive property and payroll within the state. [cite: 1]

On the R&D front, the specialized environmental stress-test chambers and the dedicated CNC machining tools utilized primarily by the engineering team to fabricate the compressor prototypes qualify for the R&D sales tax exemption under TENN. COMP. R. & REGS. 1320-05-01-.128. Once the R&D phase concludes and the product transitions to commercial assembly, the taxpayer can no longer claim the R&D exemption; however, as a principal manufacturer, they seamlessly pivot to utilizing the standard Tennessee Industrial Machinery sales tax exemption for the automated assembly lines, while continuing to accrue the 1% F&E industrial machinery credit to offset their state corporate tax liabilities. [cite: 1]

Case Study 3: Electric Vehicle (EV) Battery and Cathode Production

Historical Context and Regional Development In the 2020s, Clarksville emerged as a critical node in the national electrification and clean energy manufacturing landscape. This era of hyper-growth was catalyzed by proactive land acquisition strategies by the Clarksville-Montgomery County Industrial Development Board (IDB), which secured massive tracts of industrial property, notably the 420-acre Allensworth Farm. In 2021, at the urging of the U.S. Department of Energy to improve domestic electrification competitiveness, American-owned Microvast Power Solutions selected Clarksville for a $220 million manufacturing headquarters to produce lithium-ion battery cells and separators. Shortly thereafter, South Korean chemical giant LG Chem announced a monumental $3.2 billion investment to construct the largest EV cathode manufacturing facility in the United States on the Allensworth site. These multi-billion-dollar industries chose Clarksville due to the availability of immense, contiguous land parcels required for chemical processing, the cheap and reliable power grid managed by the TVA, and the highly attractive suite of state-sponsored economic incentives. [cite: 1]

Application of United States Federal R&D Tax Credit Laws The electric vehicle battery sector is defined by constant, rapid iterations in chemical engineering. The facilities in Clarksville house dedicated R&D departments focused on advancing battery cell technology. When chemical engineers seek to optimize the delicate ratio of nickel, cobalt, and manganese (NCM) in the cathode powder to increase overall battery energy density, extend lifecycle longevity, and mitigate the risk of thermal runaway, they are undertaking research that is fundamentally technological in nature. [cite: 1]

The technical uncertainty is acute: adjusting the chemical composition directly impacts the structural stability of the cathode matrix during charging cycles. The process of experimentation involves synthesizing hundreds of experimental chemical batches in a laboratory setting, analyzing their crystalline structures via X-ray diffraction, and subjecting sample cells to electrochemical impedance spectroscopy. The salaries of the research chemists, the vast quantities of raw chemical precursors consumed during batch testing, and the cloud computing costs required to run electrochemical simulations all qualify for the federal R&D tax credit. [cite: 1]

Application of Tennessee State Tax Incentives For megaprojects like LG Chem, the financial scale of R&D and capital investment is staggering. The State of Tennessee supports this through the Job Tax Credit, which provides a standard credit of $4,500 per qualified job created, directly offsetting up to 50% of the company’s Franchise and Excise tax liability. With LG Chem expected to create 860 high-paying jobs, this represents nearly $3.8 million in direct tax offsets. Crucially, the Tennessee Works Tax Act extended the carryforward period for these F&E credits from 15 years to 25 years, ensuring that highly capitalized companies do not lose their accrued credits before reaching full domestic profitability. [cite: 1]

Furthermore, the specific hoppers, kilns, and environmental purification systems utilized within the localized R&D pilot plants are exempt from the 7% state sales tax. Tennessee case law strongly protects these chemical manufacturing incentives. For example, in Tennessee Department of Revenue Letter Ruling #22-01, the state addressed a chemical manufacturer that sold industrial gas alongside environmental credits (such as Renewable Identification Numbers). The state ruled that the generation of auxiliary environmental credits did not disqualify the taxpayer from being classified primarily as a manufacturer, thereby preserving their right to claim the lucrative 1% industrial machinery F&E tax credit on their massive capital equipment purchases. [cite: 1]

Case Study 4: Automotive Heat Exchange and Advanced Tire Manufacturing

Historical Context and Regional Development Tennessee operates as Japan’s largest partner for Foreign Direct Investment (FDI), hosting over 200 Japanese companies that account for tens of thousands of jobs. Clarksville’s Corporate Business Park South is a microcosm of this international synergy. Global tire manufacturer Hankook Tire operates a massive facility in the city and is currently executing a $1.6 billion expansion to introduce the production of Truck Bus and Radial (TBR) tires. Adjacent to this, T.RAD, a Japanese manufacturer of advanced automotive heat exchangers used in internal combustion engines, EVs, and heavy construction equipment, is constructing a $90.2 million facility. [cite: 1]

These Tier-1 automotive suppliers localized in Clarksville to optimize supply chains for Original Equipment Manufacturers (OEMs) distributed throughout the southeastern United States. Additionally, these highly automated facilities rely heavily on the technical proficiency of military veterans transitioning from Fort Campbell, and they actively collaborate with Austin Peay State University to cultivate specialized engineering talent, as evidenced by the Hankook Tire Engineering Research Support Endowment. [cite: 1]

Application of United States Federal R&D Tax Credit Laws Automotive component manufacturing demands continuous innovation to meet fuel efficiency and safety standards. If Hankook engineers, in collaboration with APSU faculty, attempt to develop a novel synthetic rubber compound designed to significantly reduce rolling resistance (thereby increasing EV battery range) without sacrificing tread longevity, they face immense technical uncertainty. [cite: 1]

If the initial integration of the new rubber compound fails to meet the strict four-part test at the macro-level of the entire tire assembly, federal law allows the taxpayer to utilize the “Shrinking Back Rule.” This legal mechanism permits the company to apply the four-part test to a specific sub-component—in this case, the isolated tread layer—allowing the labor and supply costs associated with developing that specific layer to qualify for the federal credit, even if the broader tire design remains unchanged. For T.RAD, engineering new aluminum alloys and internal fin geometries to maximize thermal transfer between fluids without mixing them similarly qualifies as experimental engineering. [cite: 1]

Application of Tennessee State Tax Incentives In this sector, the legal distinction between true R&D and routine manufacturing operations is heavily scrutinized by state auditors. Routine quality assurance (QA) testing on tires or heat exchangers rolling off the active assembly line does not qualify for the state R&D machinery exemption. This was definitively established in Tennessee Department of Revenue Letter Rulings 25-06 and 25-07, where the state explicitly denied industrial machinery exemptions for standard QA equipment and generic Product Lifecycle Management (PLM) software used in general production. [cite: 1]

However, the proprietary, isolated testing rigs built within the facility’s dedicated engineering labs—designed solely to subject the new, experimental APSU rubber compound to extreme friction and thermal failure points—do qualify for the R&D Sales Tax Exemption under Rule 128. Because these companies also meet the “51% test” (deriving more than half their revenue from fabricating tangible property for resale), the entirety of their commercial production lines qualifies for the standard Tennessee Industrial Machinery sales tax exemption and the 1% F&E credit, representing a massive reduction in operational capital costs. [cite: 1]

Case Study 5: Advanced Hyperscale Data Centers

Historical Context and Regional Development The trajectory of the data center industry in Clarksville is a study in economic resilience. In 2008, Hemlock Semiconductor announced the construction of a $1.2 billion hyper-pure polysilicon plant to supply the booming global solar photovoltaic and microchip markets. However, due to severe industry oversupply and protracted trade disputes between the U.S. and China, the plant was permanently shuttered in 2014 before full-scale commercial production ever commenced. [cite: 1]

Recognizing the latent value of the site’s massive, purpose-built electrical infrastructure, Google purchased the facility in 2015. The technology giant invested over $600 million to completely retrofit the heavy industrial site into its 15th global, hyperscale data center. Clarksville proved to be an optimal location due to its geographic insulation from coastal natural disasters, access to vast quantities of cooling water from the Cumberland River, and the pre-existing heavy-duty electrical substations originally constructed for the polysilicon furnaces. [cite: 1]

Application of United States Federal R&D Tax Credit Laws While a data center does not manufacture tangible goods, it engages in massive software and hardware engineering efforts. If the facility’s engineering teams develop proprietary “Internal Use Software” (IUS) to optimize global server load balancing, or design custom algorithms to automate localized cooling systems to drastically reduce water consumption, these activities can qualify for the federal R&D credit. [cite: 1]

However, under federal regulations, IUS must pass the standard four-part test and an additional “High Threshold of Innovation” test, proving that the software is highly innovative, entails significant economic risk, and is not commercially available. Developing custom routing algorithms to increase data packet transmission speeds by fractions of a millisecond constitutes a valid process of experimentation. The wages of the software engineers and the massive cloud computing costs utilized in the isolated development and testing environments are fully qualifying expenses. [cite: 1]

Application of Tennessee State Tax Incentives Tennessee explicitly targets the technology sector by providing aggressive statutory carve-outs. Under T.C.A. 67-6-102(76), a facility can be designated as a “Qualified Data Center” if it meets a minimum capital investment of $100 million and creates at least 15 new full-time positions paying 150% of the state’s average occupational wage. Meeting this threshold grants the facility a comprehensive sales tax exemption on the purchase of highly expensive hardware, including servers, mainframes, networks, software, and peripheral computer devices. [cite: 1]

If the data center allocates a specific cluster of high-performance servers primarily as a sandbox environment for testing and developing new R&D algorithms, those specific servers also fall under the protection of the R&D machinery exemption. The integration of these state exemptions with the federal IUS research credits allows hyperscale facilities to drastically lower the immense capital and operational costs associated with continuous technological iteration. [cite: 1]

Detailed Analysis: United States Federal R&D Tax Credit Laws

The United States federal government established the Credit for Increasing Research Activities in 1981 to stimulate domestic innovation and ensure American industries remain highly competitive in global markets. Governed primarily by IRC Section 41 and the amortization rules of IRC Section 174, the credit provides a highly lucrative, dollar-for-dollar reduction in a company’s federal income tax liability based on their qualified research expenses (QREs). [cite: 1]

The Statutory Four-Part Test

To qualify for the Section 41 credit, a taxpayer must prove that its technical activities constitute “qualified research.” Under the stringent requirements of IRC Section 41(d), an activity must satisfy a simultaneous four-part test. Crucially, as dictated by the statute, this test must be applied separately to each specific “business component” of the taxpayer: [cite: 1]

1. The Section 174 Test: The expenditures associated with the activity must be eligible to be treated as expenses under IRC Section 174. This requires that the costs be incurred in direct connection with the taxpayer’s active trade or business, and that they represent a research and development cost in the “experimental or laboratory sense”. Routine business expenditures, such as market research, consumer surveys, and standard quality control, are explicitly disqualified. [cite: 1]
2. The Discovering Technological Information Test: The research must be undertaken for the fundamental purpose of discovering new information that is “technological in nature.” The IRS dictates that the discovery process must inherently rely on the principles of the hard sciences—specifically physical science, biological science, computer science, or engineering. Soft sciences, such as psychology or economics, do not qualify. [cite: 1]
3. The Business Component Test: The application of the discovered technological information must be intended to be useful in the development of a new or significantly improved business component of the taxpayer. The statute explicitly defines a “business component” as any product, process, computer software, technique, formula, or invention that is to be held for sale, lease, or license, or utilized by the taxpayer in the conduct of their trade or business. [cite: 1]
4. The Process of Experimentation Test: Substantially all of the research activities (defined practically by the IRS as 80% or more of the effort) must constitute elements of a process of experimentation relating to a new or improved function, performance, reliability, or quality. This is the most heavily audited aspect of the test. It requires the taxpayer to first identify a distinct technical uncertainty regarding the capability, method, or appropriate design of the business component. The taxpayer must then document a systematic process of evaluating alternatives—such as computational modeling, simulation, or structured trial and error—to overcome that specific uncertainty. [cite: 1]

Under Section 41(d)(4), Congress outlined specific activities that are statutorily excluded from qualifying as research, regardless of whether they technically meet the four-part test. These exclusions include research conducted after commercial production has commenced, the routine adaptation or duplication of existing business components, research conducted outside the United States, and funded research wherein the taxpayer does not retain substantial rights to the resulting intellectual property or does not bear the financial risk of the project’s failure. [cite: 1]

Legislative Volatility: Section 174, Section 174A, and the OBBBA

The legislative landscape surrounding the deductibility of R&E expenditures has been highly volatile in recent years, significantly impacting corporate cash flow. Historically, businesses could immediately deduct their R&E expenses in the year they were incurred. However, the Tax Cuts and Jobs Act (TCJA) of 2017 mandated a severe change: for expenditures paid or incurred in taxable years beginning after December 31, 2021, taxpayers were required to capitalize these costs and amortize them over a 5-year period for domestic research, and a 15-year period for foreign research. This effectively slowed the realization of tax benefits and increased near-term tax liabilities for innovative firms. [cite: 1]

This restrictive regime was reversed by the passage of the “One Big Beautiful Bill Act” (OBBBA) in 2025. The OBBBA added a new section, IRC Section 174A, which restored and made permanent the immediate expensing for domestic R&E expenditures. For tax years beginning after December 31, 2024, businesses can once again fully deduct their US-based R&D expenses in the year incurred. Notably, foreign R&E must still be amortized over 15 years, strongly incentivizing companies to onshore their research operations to locations like Clarksville. [cite: 1]

Furthermore, the IRS issued Revenue Procedure 2025-28, providing critical transition rules for small business taxpayers. This procedure allows eligible small businesses (generally those with average gross receipts under $31 million) to retroactively deduct any remaining unamortized domestic R&E expenses that were capitalized during the restricted 2022-2024 period, offering a massive retroactive cash infusion. [cite: 1]

Strict Evidentiary Standards and Form 6765 Revisions

The administrative burden required to claim the federal R&D credit has escalated dramatically. Following an October 2021 Chief Counsel Advice Memorandum, the IRS mandated that any refund claim must explicitly detail all business components involved, identify the specific individuals who performed the research, and articulate the precise information they sought to discover. [cite: 1]

To enforce this standard, the IRS fundamentally restructured Form 6765 (Credit for Increasing Research Activities) for the 2024 and 2025 tax years. The most significant change is the addition of “Section G—Business Component Information.” Section G requires taxpayers to provide granular, qualitative data connecting their aggregate QREs directly to distinct projects. While Section G is optional for 2024, it becomes mandatory for most taxpayers for tax years beginning in 2025. This eliminates the historical practice of estimating aggregated expenses; taxpayers must now maintain contemporaneous project-tracking systems that definitively link employee time-tracking and supply consumption to specific technical uncertainties. [cite: 1]

Federal Case Law Precedent

Recent decisions in the United States Tax Court reinforce the IRS’s aggressive stance on substantiation: [cite: 1]

• Siemer Milling Co. v. Commissioner, T.C. Memo. 2019-37: The Tax Court ruled decisively in favor of the IRS, establishing the modern precedent that taxpayers must identify discrete business components and clearly document their corresponding technical uncertainties. The court rejected the taxpayer’s reliance on broad, conclusory statements regarding their overall operational improvements. [cite: 1]
• Betz v. Commissioner (2023): The Tax Court disallowed over $500,000 in claimed R&D credits for an engineering firm designing custom air pollution control systems. The court meticulously dismantled the taxpayer’s claim, ruling that their projects failed to rise to the level of pilot models designed to resolve genuine technical uncertainty. Furthermore, the court found the taxpayer failed to document a systematic process of experimentation, noting that mere “post-installation testing” to verify functionality did not meet the Section 41 threshold. The court also invoked the “funded research” exclusion, noting the taxpayer did not retain substantial rights to the intellectual property under their client contracts, and penalized the taxpayer for relying on retroactive estimates of employee time rather than contemporaneous records. [cite: 1]

Detailed Analysis: Tennessee State R&D Tax Credit and Incentive Laws

While the federal government focuses its incentives on the labor and operational expenses associated with research, the State of Tennessee directs its tax relief toward the capitalization of innovation. Tennessee does not offer a state-level income tax credit based on research wages or standard R&D operating expenses, nor does it offer a localized payroll offset. Instead, the state relies on a highly competitive, asset-centric strategy embedded within its corporate Franchise and Excise (F&E) tax structure and its Sales and Use Tax code. [cite: 1]

The Franchise and Excise (F&E) Tax Baseline

Entities operating in Tennessee that offer limited liability protection to their owners—such as C-Corporations, S-Corporations, Limited Liability Companies (LLCs), and Limited Partnerships—are subject to the state’s Franchise and Excise taxes. The imposition of these taxes for the privilege of doing business in the state has a deep legal history, with the Excise tax upheld by the Tennessee Supreme Court in Bank of Commerce & Trust Co. v. Senter (1924) and the Franchise tax upheld in Corn v. Fort (1936). [cite: 1]

Currently, the Franchise tax is levied at a rate of 0.25% ($0.25 per $100) based on the taxpayer’s net worth at the close of the tax year. The Excise tax is levied at a flat rate of 6.5% on the taxpayer’s net earnings from business conducted within the state. [cite: 1]

In 2023, the state enacted the landmark Tennessee Works Tax Act (Public Chapter 377), which fundamentally modernized this framework to favor industrial development. Most notably, the Act transitions the state’s apportionment formula—which determines how much of a multi-state company’s income is subject to Tennessee tax—to a mandatory “Single Sales Factor” by the end of 2025. Previously, the formula heavily weighted the property and payroll located within the state. By shifting strictly to a sales factor, Tennessee effectively stopped penalizing companies like LG Chem or Trane for building massive, high-payroll R&D and manufacturing campuses within its borders. Furthermore, the Act explicitly coupled the state’s excise tax code with federal bonus depreciation rules (IRC Section 168) for assets purchased on or after January 1, 2023, allowing for aggressive early deductions on massive capital investments. [cite: 1]

The Industrial Machinery F&E Tax Credit

The cornerstone of Tennessee’s corporate incentive structure is the Industrial Machinery Tax Credit. Under T.C.A. § 67-4-2009(3), taxpayers are granted a credit against their combined F&E tax liability equal to 1% of the purchase price of qualified “industrial machinery” located within the state. This credit is powerful; it can offset up to 50% of the company’s F&E liability in any given year. Under the recent Tennessee Works Tax Act, the lifespan of this credit was vastly improved, allowing unused credits to be carried forward for up to 25 years (extended from the previous 15-year limit), ensuring that capital-heavy startups do not lose their tax benefits during early, untapped years. [cite: 1]

Crucially for innovators, the statutory definition of “industrial machinery” found in T.C.A. § 67-6-102(46)(M) was explicitly expanded to include R&D assets. The law defines qualifying machinery as: “…machinery, apparatus and equipment with all associated parts, appurtenances and accessories, including hydraulic fluids, lubricating oils, and greases necessary for operation and maintenance, repair parts and any necessary repair or taxable installation labor therefor, that is necessary to, and primarily for, the purpose of research and development.”. [cite: 1]

The Sales and Use Tax Exemption for R&D Machinery

In addition to the 1% corporate tax credit, the Tennessee General Assembly passed Public Chapter 504 (effective July 1, 2015), which established a direct, upfront Sales and Use Tax exemption for the purchase of R&D machinery and equipment. Because Tennessee’s base state sales tax is 7%, and local municipalities often add up to 2.75%, this exemption acts as an immediate capital expenditure discount of nearly 10% on all qualifying technical infrastructure. [cite: 1]

The regulatory framework governing this exemption, TENN. COMP. R. & REGS. 1320-05-01-.128, strictly defines the permissible ultimate goals of the taxpayer’s R&D activities. To qualify, the equipment must be used for basic research in a scientific field, advancing technology in a technical field, developing a new product, improving an existing product, developing new uses for a product, or designing prototypes. Research connected to historical, social science, or psychological activities is expressly forbidden. [cite: 1]

Unlike the broader industrial machinery exemptions intended for traditional production lines, a company does not need to be a principal manufacturer (i.e., deriving more than 50% of its revenue from fabricating tangible personal property for resale) to claim the R&D machinery exemption. To legally execute this exemption, the taxpayer must preemptively submit Form RV-F1325101 to the Department of Revenue, detailing the nature of the research and listing the specific machinery. Upon approval, the state issues an R&D Exemption Certificate, which the taxpayer must present to vendors at the point of sale. [cite: 1]

Tennessee Case Law and Administrative Letter Rulings

The Tennessee Department of Revenue (DOR) stringently audits the boundaries of these exemptions, frequently issuing Letter Rulings that clarify the precise definitions of “manufacturing,” “processing,” and “research and development.” [cite: 1]

• The “Primarily For” Standard (DOR Letter Rulings 25-06 and 25-07): In September 2025, a frozen food manufacturer sought the R&D machinery exemption for Quality Assurance (QA) testing equipment and highly sophisticated Product Lifecycle Management (PLM) computer networks. The DOR decisively rejected the claim in both rulings. The Department noted that while the PLM software was advanced, it was utilized for multiple operational purposes across the facility, including standard production management and routine QA testing. Therefore, it failed the strict statutory requirement of T.C.A. § 67-6-102(46)(M) that the equipment be used “primarily for the purpose of research and development”. [cite: 1]
• Defining the Principal Business (DOR Letter Ruling 22-01): An industrial gas producer sought the 1% industrial machinery F&E credit. Auditors questioned the claim because a significant portion of the company’s revenue was derived from selling intangible environmental credits (Renewable Identification Numbers and Low Carbon Fuel Standard credits) rather than the physical gas itself. The DOR ruled in favor of the taxpayer, establishing that because the intangible credits were derived directly from the physical manufacturing process, the facility’s “principal business” remained the fabrication of tangible personal property, fully preserving their right to the industrial machinery credit. [cite: 1]
• Judicial Expansion of “Processing” (Alsco Inc. v. Department of Revenue): The Tennessee Court of Appeals recently overruled a long-standing DOR policy that had excluded commercial laundering and sanitation from the definition of industrial “processing.” The court ruled that the taxpayer’s highly specialized, industrial-scale sanitation operations fundamentally altered the state of the tangible property, thereby legally constituting processing and opening the door for non-traditional industrial facilities to claim the machinery exemptions. [cite: 1]
• The Maintenance Exclusion (Norandal USA v. Commissioner): In a critical appellate ruling defining the boundaries of the exemption, the court evaluated massive, multi-ton roll grinders utilized within an aluminum manufacturing plant. The court sided with the Commissioner, ruling that because the grinders were used to maintain the primary manufacturing equipment rather than directly fabricate the aluminum product, they fell under the “equipment used for maintenance” exception. Consequently, all supplies purchased to operate the grinders were fully subject to state sales tax. [cite: 1]

Strategic Final Thoughts and Recommendations

The industrial ecosystem of Clarksville, Tennessee, represents a masterclass in regional economic development harmonized with aggressive tax strategy. By transforming its historical reliance on agriculture and river trade into a centralized hub for advanced metallurgy, climate control engineering, EV battery chemistry, and hyperscale data processing, Clarksville has curated an environment where businesses can maximize their return on technical innovation. [cite: 1]

To fully optimize these incentives, corporate tax directors operating in Montgomery County must adopt a bifurcated approach. At the federal level, companies must adhere to the stringent documentation standards established by the Siemer Milling and Betz decisions. With the mandatory implementation of Form 6765’s Section G in 2025, reliance on high-level estimates of engineering time is functionally obsolete. Taxpayers must deploy robust, contemporaneous tracking systems that explicitly bind QREs—wages, supplies, and contract research—to discrete business components and clearly defined technical uncertainties. Concurrently, companies must capitalize on the 2025 OBBBA legislation by immediately expensing their domestic Section 174 R&E costs, providing a massive injection of operational cash flow compared to the restrictive amortization rules of previous years. [cite: 1]

At the state level, businesses must rigorously structure their capital acquisitions to exploit Tennessee’s asset-focused code. Because the state lacks a direct R&D payroll credit, Clarksville industries must aggressively partition their procurement strategies. Equipment utilized explicitly for experimentation must be legally segregated from routine QA or maintenance apparatuses—as demonstrated by DOR Rulings 25-06 and 25-07—to secure the upfront ~10% R&D Sales Tax Exemption under Public Chapter 504. As these experimental products successfully transition into full-scale commercial manufacturing, facilities must then seamlessly pivot to the 1% Industrial Machinery Franchise and Excise Tax Credit, utilizing the newly expanded 25-year carryforward provisions of the Tennessee Works Tax Act to systematically eliminate their corporate tax liabilities over the coming decades. [cite: 1]

The information in this study is current as of the date of publication, and is provided for information purposes only. Although we do our absolute best in our attempts to avoid errors, we cannot guarantee that errors are not present in this study. Please contact a Swanson Reed member of staff, or seek independent legal advice to further understand how this information applies to your circumstances. [cite: 1]