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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-K

For the Fiscal Year Ended December 31, 2021

OR

Commission File No. 001-35456

ALLISON TRANSMISSION HOLDINGS, INC.

(Exact Name of Registrant as Specified in Its Charter)

One Allison Way

Indianapolis, IN 46222

(Address of Principal Executive Offices and Zip Code)

(317) 242-5000

(Registrant’s Telephone Number, Including Area Code)

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☒ No ☐

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐ No ☒

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

The aggregate market value of the voting and non-voting stock held by non-affiliates was approximately $4,182 million as of June 30, 2021.

As of February 3, 2022, there were 97,819,154 shares of Common Stock outstanding.

Documents Incorporated by Reference

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INDEX

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Cautionary Note Regarding Forward-Looking Statements

This Annual Report on Form 10-K contains forward-looking statements. The words “believe,” “expect,” “anticipate,” “intend,” “estimate” and other expressions that are predictions of or indicate future events and trends and that do not relate to historical matters identify forward-looking statements. You should not place undue reliance on these forward-looking statements. Although forward-looking statements reflect management’s good faith beliefs, reliance should not be placed on forward-looking statements because they involve known and unknown risks, uncertainties and other factors, which may cause actual results, performance or achievements to differ materially from anticipated future results, performance or achievements expressed or implied by such forward-looking statements. Forward-looking statements speak only as of the date the statements are made. We undertake no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events, changed circumstances or otherwise. These forward-looking statements are subject to numerous risks and uncertainties, including, but not limited to: the duration and spread of the COVID-19 pandemic, including new variants of the virus and the pace and availability of vaccines and boosters, mitigating efforts deployed by government agencies and the public at large, and the overall impact from such outbreak on economic conditions, financial market volatility and our business, including but not limited to the operations of our manufacturing and other facilities, the availability of labor, our supply chain, our distribution processes and demand for our products and the corresponding impacts to our net sales and cash flow; increases in cost, disruption of supply or shortage of labor, freight, raw materials or components used to manufacture or transport our products or those of our customers or suppliers, including as a result of the COVID-19 pandemic; our participation in markets that are competitive; our ability to prepare for, respond to and successfully achieve our objectives relating to technological and market developments, competitive threats and changing customer needs, including with respect to electric hybrid and fully electric commercial vehicles; the highly cyclical industries in which certain of our end users operate; uncertainty in the global regulatory and business environments in which we operate; the concentration of our net sales in our top five customers and the loss of any one of these; the failure of markets outside North America to increase adoption of fully automatic transmissions; the success of our research and development efforts, the outcome of which is uncertain; U.S. and foreign defense spending; risks associated with our international operations, including increased trade protectionism; general economic and industry conditions; the discovery of defects in our products, resulting in delays in new model launches, recall campaigns and/or increased warranty costs and reduction in future sales or damage to our brand and reputation; our ability to identify, consummate and effectively integrate acquisitions and collaborations; labor strikes, work stoppages or similar labor disputes, which could significantly disrupt our operations or those of our principal customers or suppliers; and risks related to our indebtedness.

Important factors that could cause actual results to differ materially from our expectations are disclosed under Part I, Item 1A, “Risk Factors” in this Annual Report on Form 10-K. All written and oral forward-looking statements attributable to us, or persons acting on our behalf, are expressly qualified in their entirety by the cautionary statements as well as other cautionary statements that are made from time to time in our other Securities and Exchange Commission filings or public communications. You should evaluate all forward-looking statements made in this Annual Report on Form 10-K in the context of these risks and uncertainties.

Certain Trademarks

This Annual Report on Form 10-K includes trademarks, such as Allison Transmission, eGen Flex, eGen Power, FracTran, TerraTran, ReTran and Walker Die Casting, which are protected under applicable intellectual property laws and are our property and/or the property of our subsidiaries. This report also contains trademarks, service marks, copyrights and trade names of other companies, which are the property of their respective owners. We do not intend our use or display of other companies’ trademarks, service marks, copyrights or trade names to imply a relationship with, or endorsement or sponsorship of us by, any other companies. Solely for convenience, our trademarks and trade names referred to in this report may appear without the ® or TM symbols, but such references are not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or the rights of the applicable licensor to these trademarks and trade names.

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PART I.

ITEM 1. Business

Overview

Allison Transmission Holdings, Inc. and its subsidiaries (“Allison,” the “Company,” “we,” “us” or “our”) design and manufacture vehicle propulsion solutions, including commercial-duty on-highway, off-highway and defense fully automatic transmissions and electric hybrid and fully electric systems. The business was founded in 1915 and has been headquartered in Indianapolis, Indiana since inception. Allison is traded on the New York Stock Exchange under the symbol “ALSN”.

We have approximately 3,400 employees. Although approximately 76% of revenues were generated in North America in 2021, we have a global presence by serving customers in Asia, Europe, South America and Africa. We serve customers through an independent network of approximately 1,400 independent distributor and dealer locations worldwide.

Throughout 2021, the COVID-19 pandemic continued to cause supply chain, labor and raw material constraints that created volatility in our business performance and impacted global markets and supply chains. As a result, we experienced, and expect to continue to experience, raw material and component part price inflation, increased freight and logistics costs and increased overtime expense as a result of labor shortages. In addition, despite increased customer demand our net sales for 2021 were negatively impacted as a result of our customers’ inability to secure components from the broader commercial vehicle supply base which resulted in reduced commercial vehicle build schedules. We expect that commercial vehicle build schedules will continue to be negatively impacted by the availability of components in 2022.

To limit the spread of COVID-19, governments continue to take various actions including the administration or mandate of vaccinations, travel bans and restrictions, quarantines, curfews, stay-at-home orders, social distancing guidelines and business shutdowns and closures. We are also continuing to take a variety of measures to promote the safety and security of our employees and to maintain operations with as minimal impact as possible to our stakeholders, and as a result, we have been able to continue our manufacturing operations and deliver our products to customers.

Our Business

We are the world’s largest manufacturer of fully automatic transmissions for medium- and heavy-duty commercial vehicles and medium- and heavy-tactical U.S. defense vehicles and a leader in electrified propulsion systems. Allison products are used in a wide variety of applications, including on-highway trucks (distribution, refuse, construction, fire and emergency), buses (primarily school and transit), motorhomes, off-highway vehicles and equipment (primarily energy, mining and construction applications) and defense vehicles (tactical wheeled and tracked). We believe the Allison brand is one of the most recognized in our industry as a result of the performance, reliability and fuel efficiency of our propulsion solutions and is associated with high quality, durability, vocational value, technological leadership and superior customer service.

We introduced the world’s first fully automatic transmission for commercial vehicles over 70 years ago. Since that time, we have driven the trend in North America and other parts of the world towards increasing automaticity by targeting a diverse range of commercial vehicle vocations. Allison products are optimized for the unique performance requirements of end users, which typically vary by vocation. Our products are highly engineered, requiring advanced manufacturing processes, and employ complex software algorithms for our propulsion system controls to maximize end user performance. We have developed over 100 different models that are used in more than 2,500 different vehicle configurations and are compatible with more than 500 combinations of engine brands,

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models and ratings (including diesel, gasoline, natural gas and other alternative fuels). Additionally, we have created thousands of unique Allison-developed calibrations available to be used with our control modules.

Our Industry

Commercial vehicles typically employ one of three transmission types: manual, automated manual or fully automatic. Manual and automated manual transmissions ("AMT") are the most prevalent transmission type used in Class 8 tractors in North America. Manual transmissions are the most prevalent in medium- and heavy-duty commercial vehicles, generally, outside North America. Manual transmissions utilize a disconnect clutch causing power to be interrupted during each gear shift resulting in energy loss-related inefficiencies and less work being accomplished for a given amount of fuel consumed. In long-distance trucking, this power interruption is not a significant factor, as the manual transmission provides its highest degree of fuel economy during steady-state cruising. However, steady-state cruising is only one part of the duty cycle. When the duty cycle requires a high degree of “start and stop” activity or speed transients, as is common in many vocations as well as in urban environments, we believe manual transmissions result in reduced performance, lower fuel efficiency, lower average speed for a given amount of fuel consumed and inferior ride quality. Moreover, the clutches must be replaced regularly, resulting in increased maintenance expense and vehicle downtime. Manual transmissions also require a skilled driver to operate the disconnect clutch when launching the vehicle and shifting gears. AMTs are manual transmissions that feature automated operation of the disconnect clutch. Fully automatic transmissions utilize technology that smoothly shifts gears instead of a disconnect clutch, thereby delivering uninterrupted power to the wheels during gear shifts and requiring minimal driver input. These transmissions deliver superior acceleration, higher productivity, increased fuel efficiency, reduced operating costs, less driveline shock and smoother shifting relative to both manual transmissions and AMTs in vocations with a high degree of “start and stop” activity, as well as in urban environments.

Emerging technologies in commercial-duty propulsion solutions include electric hybrid and fully electric propulsion solutions in certain end markets and are in part driven by efforts to reduce fuel consumption, noise and greenhouse gas emissions. Fully electric powertrains differ from electric hybrid powertrains because they only propel the vehicle with an electric motor; while electric hybrids generally utilize both a conventional internal combustion power source and powertrain as well as the means to propel the vehicle electrically. While both emerging technologies are gaining use in automotive markets and electric hybrids and fully electric propulsion solutions have gained use in the transit bus market, fully electric propulsion solutions remain in a developmental phase in the medium- and heavy-duty commercial vehicle market.

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Our Served Markets

We sell our propulsion solutions globally for use in medium- and heavy-duty on-highway commercial vehicles, off-highway vehicles and equipment and defense vehicles. In addition to the sale of propulsion solutions, we also sell branded replacement parts, support equipment, aluminum die cast components and other products necessary to service the installed base of vehicles utilizing our solutions. The following table provides a summary of our business by end market, for the fiscal year ended December 31, 2021.

Refer to "NOTE 19. Concentration of Risk” in Part II, Item 8., of this Annual Report on Form 10-K for additional information on our significant original equipment manufacturer (“OEM”) customers.

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North America

On-Highway. We are the largest manufacturer of fully automatic transmissions for the on-highway medium- and heavy-duty commercial vehicle market in North America. The following is a summary of our on-highway net sales by vehicle class in North America.

Our core North American on-highway market includes Class 4-5, Class 6-7 and Class 8 straight trucks, conventional transit, shuttle and coach buses, school buses and motorhomes. Class 8 trucks are subdivided into two markets: straight and tractor. Class 8 straight trucks are those with a unified body (e.g., refuse, construction, and dump trucks), while tractors have a vehicle chassis that is separable from the trailer they pull. We have been supplying transmissions for Class 8 straight trucks for decades, and it is a core end market for us. We have limited exposure to the Class 8 tractor market because lower priced manual transmissions and AMTs generally meet the needs of these vehicles which are primarily used in long distance hauling.

We also provide electric hybrid and fully electric propulsion solutions within the North American on-highway market. The interest in conserving fuel and reducing greenhouse gas emissions is driving demand for more fuel-efficient commercial vehicles. Our electric hybrid and fully electric propulsion customers include bus and truck applications. We compete primarily with BAE Systems plc and manufacturers of fully electric propulsion solutions such as Dana Incorporated and Meritor, Inc. as well as certain vertically integrated OEMs.

We sell substantially all of our propulsion solutions in the North American on-highway market to OEMs. These OEMs, in turn, install our propulsion solutions in vehicles in which our product is either the exclusive propulsion solution available or is specifically requested by end users. In 2021, OEM customers representing over 95% of our North American on-highway unit volume participated in long-term agreements (“LTAs”) with us. Generally, these LTAs offer the OEM customer defined levels of mutual commitment with respect to growing Allison’s presence in the OEMs’ products and promotional efforts, pricing and sharing of commodity cost risk. The length of our LTAs is typically between three and five years. We often compete in this market against independent manufacturers of manual transmissions, AMTs, electric hybrid and fully electric propulsion solutions, fully automatic transmissions manufactured by Ford Motor Company (“Ford”), ZF Friedrichshafen AG (“ZF”) and Voith GmbH (“Voith”) and against vertically integrated OEMs in certain weight classes that use their own internally manufactured transmissions in certain vehicles.

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The following table presents a summary of our market share by vehicle class in the North America On-Highway end market.

Off-Highway. We have provided products used in vehicles and equipment that serve energy, mining and construction applications in North America for over 70 years. Off-highway energy applications include hydraulic fracturing equipment, well-stimulation equipment, pumping equipment, and well-servicing rigs, which often use a fully automatic transmission to propel the vehicle and drive auxiliary equipment. We supply our heavy duty off-highway transmissions to producers of well-stimulation and well-servicing equipment. Competition includes Caterpillar Inc. (“Caterpillar”) and Twin Disc, Inc. (“Twin Disc”).

We also provide heavy-duty transmissions used in mining trucks, specialty vehicles and construction vehicles. Mining applications include trucks used to haul various commodities and other products, including rigid dump trucks, underground trucks and long-haul tractor trailer trucks with load capacities between 40 to 110 tons. Our major competitors in this end market are Caterpillar and Komatsu Ltd. (“Komatsu”), both of which are vertically integrated and manufacture fully automatic transmissions for their own vehicles. Specialty vehicles using our heavy-duty transmissions include airport rescue and firefighting vehicles and heavy-equipment transporters. Our major competitor in this end market is Twin Disc. Construction applications include articulated dump trucks, with Caterpillar, Volvo Group (“Volvo”) and ZF as competitors.

Outside North America

Outside North America we serve several different markets, including: Asia-Pacific, Europe, Middle East, Africa (collectively, “EMEA”), and South America.

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On-Highway. We are the largest manufacturer of fully automatic transmissions for the commercial vehicle market outside of North America. We also provide electric hybrid and fully electric propulsion solutions within the outside North America on-highway market. While the use of fully automatic transmissions in the medium- and heavy-duty commercial vehicle market has been widely accepted in North America, markets outside North America continue to be dominated by manual transmissions. Where adopted, fully automatic transmission-equipped medium- and heavy-duty commercial vehicles are concentrated in certain vocational end markets. We often compete in this market against independent manufacturers of manual transmissions, AMTs, electric hybrid and fully electric propulsion solutions, fully automatic transmissions manufactured by ZF, Voith, and Shaanxi Fast Gear Co., Ltd. and against vertically integrated OEMs. The following is a summary of our on-highway net sales by region outside of North America.

Asia-Pacific. Our key Asia-Pacific markets include China, Japan, South Korea and India; however, we actively participate in several other important Asia-Pacific countries including Australia, Thailand, Malaysia, Taiwan and Indonesia, which are primarily importers of commercial vehicles. Within Asia-Pacific, our sales efforts are principally focused on the transit bus and vocational truck markets. Currently, manual transmissions are the predominant transmissions used in commercial vehicles in the Asia-Pacific region. In China, government subsidies and regulations by governmental entities continue to drive the development and adoption of fully electric propulsion solutions for use in the bus and truck markets.

Europe, Middle East, Africa. EMEA is composed of several different markets, each of which differs from our core North American market by the degree of market maturity, sophistication and acceptance of fully automatic transmission and electric propulsion solution technology. Within Europe, we serve Western European developed markets, as well as Russian and Eastern European emerging markets, principally in the refuse, emergency, bus, coach, distribution and utility markets. Competition in Western Europe is most notably characterized by a high level of vertical powertrain integration with OEMs often utilizing their own manual transmissions and AMTs in their vehicles, and increasingly electric hybrid and fully electric propulsion solutions. The Middle East and Africa regions are generally characterized by very limited local vehicle production, with imports from China, Europe, India, South America, Turkey and the U.S. accounting for the majority of vehicles.

South America. The South American region is characterized by a high level of OEM integration, with captive manual transmission and AMT manufacturing. Currently, manual transmissions are the predominant transmissions used in commercial vehicles in South America.

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Off-Highway. The following is a summary of our off-highway net sales by region outside of North America.

Asia-Pacific. Off-highway markets in Asia are shared by energy, mining and construction applications. Our primary competitors are Caterpillar, Danyang Winstar Auto Parts Co., Ltd., Twin Disc and Xi’an FC Intelligence Transmission Co. Ltd. in energy applications; Caterpillar, Danyang Winstar Auto Parts Co., Ltd. and Komatsu in mining applications; and Caterpillar, Volvo and ZF in construction applications.

Europe, Middle East, Africa. Our off-highway markets in EMEA are mining and construction. Our major off-highway competitors are Caterpillar and Komatsu, both of which are vertically integrated manufacturers of off-highway mining vehicles, including the specific fully automatic transmission used in their mining trucks. A typical construction application is a rigid or articulated dump truck, with competition from Caterpillar, Dana Incorporated, Volvo and ZF transmissions.

Defense

We have a long-standing relationship with the U.S. Department of Defense (the “DOD”) dating back to 1946, when we began developing our first-generation tank transmission. Today, we sell substantially all of the transmissions for medium- and heavy-tactical wheeled vehicle platforms including the Joint Light Tactical Vehicle, Light Armored Vehicle, Stryker Armored Vehicle, Mine Resistant Ambush Protected Vehicle, the Family of Medium Tactical Vehicles, Heavy Expanded Mobility Tactical Trucks, Palletized Loading System for Heavy Dump Truck and Heavy Equipment Transporters. Transmissions for our wheeled vehicle platforms are typically sold to OEMs.

We also supply more than half of the tracked vehicle transmissions in U.S. Army armored brigades directly to the DOD, including the Abrams M1A2 Main Battle Tank, Joint Assault Bridge, Assault Breacher Vehicles and the M113A3 Armored Personnel Carrier family of vehicles. We also sell transmissions to the DOD for the U.S. Army Abrams Tank sustainment, as well as for certain Abrams Tank customers outside North America. Additionally, we sell parts kits to licensees for the production of transmissions for tracked vehicles manufactured outside North America, and our defense products are in approximately 110 countries around the world. See Part I, Item 1A, “Risk Factors” of this Annual Report on Form 10-K for a discussion of risks associated with our contracts with the DOD.

Globally, we face competition primarily from Renk AG/Renk America, SAPA S.p.A, S&T Dynamics and QinetiQ Group plc for supply of tracked vehicle transmissions. Additionally, we face competition from ZF and AM General in certain defense wheeled vehicles using automatic transmissions and numerous manual transmission suppliers.

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Service Parts, Support Equipment and Other

Our service parts, support equipment and other end market is comprised of: Allison-branded service parts and transmission fluids, aluminum die cast components, extended transmission coverage, remanufactured transmissions, royalties, saleable engineering and support equipment. The aftermarket provides us with a relatively stable source of revenues as the installed base of vehicles and equipment utilizing our solutions continues to grow. The need for replacement parts is driven by normal vehicle and equipment maintenance requirements. Uninterrupted operation is generally critical for end users’ profitability. In addition, in 2019 we began selling aluminum die casting components following our acquisition of Walker Die Casting.

The sale of Allison-branded parts and fluids, remanufactured transmissions and support equipment is fundamental to our brand promise. We have assembled a worldwide network of approximately 1,400 independent distributor and dealer locations to sell, service and support our solutions. As part of our brand strategy, our distributors and dealers are required to sell genuine Allison-branded parts. Within the aftermarket, we offer remanufactured transmissions under our ReTran brand, which provides a cost-effective alternative for transmission repairs and replacements. We also provide support equipment to our OEMs to assist in installing new Allison solutions into vehicles, and, therefore, sales of support equipment are dependent upon sales of new solutions. The competition for service parts and ReTran transmissions comes from a variety of smaller-scale companies sourcing non-genuine “will-fit” parts from unauthorized manufacturers. These “will-fit” parts often do not meet our product specifications, and therefore may be of lesser quality than genuine Allison parts.

Our Product Offerings

Allison transmissions and electric propulsion solutions are sold under the Allison Transmission brand name and remanufactured transmissions are sold under the ReTran brand name. The following is a summary of our product lines.

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Product Development and Engineering

We maintain product development and engineering capability dedicated to the design, development, refinement and support of our fully automatic transmissions and electric hybrid and fully electric propulsion systems. We believe our customers expect our products to provide unparalleled performance and value defined in various ways, including delivering maximum cargo in minimum time, using the least amount of fuel possible while employing the fewest vehicles possible and experiencing maximum vehicle uptime. In response to those needs and the evolving customer focus on fuel efficiency and reduced emissions, we provide vehicle specification guidelines, propulsion control software and mechanical components to optimize fuel economy while delivering desired vehicle performance.

Further, we are developing new technology to improve fuel efficiency and fuel economy by allowing engines to operate more efficiently and at lower speeds to avoid consuming fuel without compromising performance. Some examples of these development efforts include the announcements of our first 9-speed transmission and the uprated variant of our existing 3000 Series transmission for the on-highway day cab tractor end-market. We also pioneered electric hybrid-propulsion in commercial vehicles and beginning in 2019, we announced our fully electric propulsion solutions. Building on our existing engineering capabilities and technology acquired in 2019 we continue to enhance our existing electric hybrid-propulsion system with additional electrification features, including our eGen Flex product which has the ability to operate in electric only mode for up to 10 miles. We also continue to develop and enhance new alternative technologies for use in our global commercial vehicle markets, including fully electric centrally-located drive and electrified-axle solutions such as our eGen Power family of products. Finally, our product development and engineering efforts also extend into our Off-Highway and Defense end-markets through initiatives to develop more efficient and higher-horsepower hydraulic fracturing and mining transmissions such as FracTran and TerraTran, as well as new cross-drive transmissions for tracked applications, such as the Next Generation Electrified Transmission that enables electric hybrid propulsion and electric only silent maneuverability. From time to time, we also acquire certain licenses to provide us with technology to complement our portfolio of products and product initiatives.

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Sales and Marketing Organization

Our sales and marketing effort is organized along geographic and customer lines and is comprised of marketing, sales and service professionals, supported by application engineers worldwide. In North America, selling efforts in the on-highway end market are organized by distributor area responsibility, OEM sales and, for our large end users, national accounts. Outside North America, we manage our sales, marketing, service and application engineering professionals through regional areas of responsibility. These regional management teams distribute OEM service and application engineering resources globally. We manage our defense products sales, marketing and service geographically with North America and Outside North America sales supported by and application engineering through professionals based in Indianapolis, Indiana.

We have developed a marketing strategy to reach OEM customers as well as end users. We target our end users primarily through marketing activities by our sales staff, who directly call on end users and attend local trade shows, targeting specific vocations globally and through our plant tour programs, where end users may test our products on our Indianapolis test track and our enhanced customer experience demonstration track at our Hungary facility.

While our marketing management uses the term “customer” interchangeably for OEMs and end users, the primary objective of our marketing strategy is to create demand for propulsion solutions through:

The process is interactive, as Allison representatives, Allison distributors, OEMs and dealers educate customers and respond to the specific applications, requirements and needs of numerous specialty markets.

Similarly, we work with customers, dealers and OEMs to educate, improve and simplify how they specify vehicles and vehicle systems in order to optimize vehicle performance and fuel consumption. Our field organization also works closely with distributors who, in turn, work with dealers to provide end users with education, parts, service and warranty support. The defense group focuses on industry OEMs and collaborative dialogue with OEMs and government leaders to understand program requirements and determine our long-term product development strategy.

Manufacturing

Our manufacturing strategy provides for distributed capability in manufacturing and assembly of our products for the global commercial vehicle market. Our primary manufacturing facilities, located in Indianapolis, Indiana, consist of approximately 2.3 million square feet of usable manufacturing space in six plants. We also have established customization and parts distribution in the United States, The Netherlands, Brazil, China, Hungary, India and Japan. Our high volume on-highway products are produced in multiple global locations (United States, Chennai, India and Szentgotthard, Hungary), while off-highway, electric hybrid propulsion and defense tracked products are produced in Indianapolis and fully electric propulsion solutions are produced in Auburn Hills, Michigan. In addition, our aluminum die cast components are produced in Lewisburg, Tennessee.

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Suppliers and Raw Materials

A significant amount of the part numbers that make up our propulsion solutions are purchased from outside suppliers, and during 2021, we purchased approximately $851 million of direct materials and components from outside suppliers. The largest elements of our direct spending are aluminum and steel castings and forgings that are formed by our suppliers into our larger components and assemblies for use in our propulsion solutions. Our spending on aluminum and steel raw materials directly and indirectly through our purchase of these components constituted approximately 20% of our direct material and component costs in 2021. The balance of our direct and indirect materials and components costs are primarily composed of value-added services and conversion costs. Our supply contracts, along with an intensive supplier selection and performance monitoring process, have enabled us to establish and maintain close relationships with suppliers and have contributed to our overall operating efficiency and quality.

Intellectual Property

Patents, trademarks, and other proprietary rights are important to the continued success of our business. We also rely upon trade secrets, know-how, continuing technological innovation and licensing opportunities to develop and maintain our competitive position. We protect our proprietary rights through a variety of methods, including confidentiality agreements and proprietary information agreements with suppliers, employees, consultants and others who may have access to our proprietary information. We own and have licensing arrangements for a number of U.S. and foreign patents related to our products and business. We do not consider our business to be dependent on any single patent, nor will the expiration of any single patent materially affect our business. Our current patents will expire over various periods and we continue to file new patent applications on newly-developed technology.

Seasonality

Overall, the demand for our products is relatively consistent over the year. However, in typical market conditions, the North American truck market experiences a higher level of production in the first half of the year due to fewer holidays and the practice of plant shutdowns in July and December. Due to ongoing supply chain and labor constraints caused by the COVID-19 pandemic, demand for our products may not align with the demand we have experienced during typical market conditions.

Human Capital

At Allison, we believe in the power of our people, our processes and our products. For more than 100 years, we have built our business on these values: Quality, Customer Focus, Integrity, Innovation, and Teamwork. We use a variety of human capital measures in managing our business, including: workforce demographics; inclusion and diversity; and employee health and safety.

Workforce Demographics. Our people continue to be a critical component in our continued success, the delivery of our values and the execution of our growth initiatives. As of December 31, 2021, we had a highly skilled workforce of approximately 3,400 employees, with approximately 90% of those employees in the U.S. Approximately 46% of our U.S. employees are represented by the International Union, United Automobile, Aerospace and Agricultural Implement Workers of America (“UAW”) and are subject to a collective bargaining agreement. In December 2017, we entered into a six-year collective bargaining agreement with UAW Local 933 that expires in November 2023. There have been no strikes or work stoppages due to Allison-specific issues in over 30 years.

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Inclusion and Diversity. Allison recognizes the power of different thought, accepts and respects each individual and strives to create an inclusive workplace where everyone can reach their full potential, driving innovation and business results. Our inclusion and diversity efforts in 2021 included the participation by approximately 1,000 employees in unconscious bias training, continuing our speaker series to facilitate dialogue about inclusion and diversity, continuing to increase our focus on the recruitment of underrepresented groups including by participating in career fairs with Historically Black Colleges and Universities, Hispanic institutions, veterans and people with disabilities and establishing a virtual mentoring program to connect team members from different offices, departments and backgrounds.

Employee Health & Safety. Allison’s overriding priority is to protect the health and safety of each employee. As part of our health and safety programs, employees participate in training focused on this topic and metrics are reviewed regularly, including the number of injury incidents that occur and those incidents that result in lost work days. For 2021, we achieved an overall recordable rate of 1.94, meaning that for every 100 employees, 1.94 employees incurred an injury that resulted in recordable medical treatment and the number of lost work days was 0.53, meaning that for every 100 employees, 0.53 individuals experienced an incident that resulted in days away from work.

Government Regulations

We are subject to a variety of federal, state, local and foreign laws and regulations, including those governing the discharge of pollutants into the air or water, the management and disposal of hazardous substances or wastes, and the cleanup of contaminated sites. Some of our operations require environmental permits and controls to prevent and reduce air and water pollution. These permits are subject to modification, renewal and revocation by issuing authorities. In addition, certain of our products and our customer’s products are subject to certification requirements by a variety of regulatory bodies. We believe we are in substantial compliance with all material environmental laws and regulations applicable to our plants and operations. Historically, our annual costs of achieving and maintaining compliance with environmental, health and safety requirements have not been material to our financial results.

Increasing global efforts to control emissions of carbon dioxide, methane, ozone, nitrogen oxide and other greenhouse gases and pollutants, as well as the shifting focus of regulatory efforts towards total emissions output, have the potential to impact our facilities, costs, products and customers. The U.S. Environmental Protection Agency (“EPA”) has taken action to control greenhouse gases from certain stationary and mobile sources. In addition, several states have taken steps, such as adoption of cap and trade programs or other regulatory systems, to address greenhouse gases. There have also been international efforts seeking legally binding reductions in emissions of greenhouse gases. These developments and further actions that may be taken in the U.S. and in other countries, states or provinces could affect our operations both positively and negatively (e.g., by affecting the demand for or suitability of some of our products).

We also may be subject to liability as a potentially responsible party under the Comprehensive Environmental Response, Compensation and Liability Act and similar state or foreign laws for contaminated properties that we currently own, lease or operate or that we or our predecessors have previously owned, leased or operated, and sites to which we or our predecessors sent hazardous substances. Such liability may be joint and several so that we may be liable for more than our share of any contamination, and any such liability may be determined without regard to causation or knowledge of contamination. We or our predecessors have been named potentially responsible parties at contaminated sites from time to time. We do not anticipate our liabilities relating to contaminated sites will be material to our financial results.

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Competition

We compete on the basis of product performance, quality, price, distribution capability, service and fuel efficiency, in addition to other factors. We face competition from numerous manufacturers of various types of propulsion solutions for commercial vehicles. Furthermore, we face an increasing amount of competition from vertical integration, as some of our customers are OEMs that manufacture propulsion solutions for their own products. Despite their propulsion solutions manufacturing capabilities, we believe that our existing OEM customers have chosen to purchase certain propulsion solutions from us due to the quality, reliability and strong brand of our propulsion solutions and in order to limit fixed costs, minimize production risks and maintain company focus on commercial vehicle design, production and marketing.

Corporate Information

Allison Transmission Holdings, Inc. was incorporated in Delaware on June 22, 2007. Our principal executive offices are located at One Allison Way, Indianapolis, IN 46222 and our telephone number is (317) 242-5000. Our internet address is www.allisontransmission.com. We file annual, quarterly and current reports, proxy statements and other documents with the United States Securities and Exchange Commission (“SEC”), under the Securities Exchange Act of 1934, as amended (the “Exchange Act”). These periodic and current reports and all amendments to those reports are available free of charge on the investor relations page of our website at http://ir.allisontransmission.com as soon as reasonably practicable after we electronically file them with, or furnish them to, the SEC. We have included our website address throughout this filing as textual references only. The information contained on, or accessible through, our website is not incorporated into this Annual Report on Form 10-K. The SEC also maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC at http://www.sec.gov.

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ITEM 1A. Risk Factors

The following is a cautionary discussion of risks, uncertainties and assumptions that we believe are material to our business. In addition to the factors discussed elsewhere in this Annual Report on Form 10-K, the following are the material factors that, individually or in the aggregate, we believe could make our actual results differ materially from those described in any forward-looking statements.

Risks Related to Our Business and Operations

We participate in markets that are competitive, and our competitors’ actions could have a material adverse effect on our business, results of operations and financial condition.

Our business operates in competitive markets. We compete against other existing or new global manufacturers of transmissions and propulsion solutions for commercial vehicles on the basis of product performance, quality, price, distribution capability, service and fuel efficiency in addition to other factors. In addition, we compete with manufacturers developing alternative technologies, including fully electric propulsion solutions, that may or may not require a transmission. In addition, regulations enacted and subsidies offered by governmental entities continue to drive the development and adoption of various alternative technologies, including electric propulsion solutions. If the pace of adoption of electric vehicles proceeds faster than we are anticipating, we may not be in a position to meet customer demand or our competitors may be better positioned to meet customer demand, which may result in a decline in our market share or negatively impact our ability to execute our growth initiatives. Actions by our competitors or accelerated adoption of electric vehicles, in particular if our competitors are able to develop, validate and release new technologies more quickly than we do, could also lead to downward pressure on prices and/or a decline in our market share, either or both of which could adversely affect our results.

In addition, some of our customers or future customers are OEMs that manufacture or could in the future manufacture transmissions, propulsion solutions or alternate technologies, including electric propulsion solutions, for their own products. Despite their manufacturing capabilities, our existing OEM customers have chosen to purchase certain transmissions and propulsion solutions from us due to customer demand, resulting from the quality of our products and in order to reduce fixed costs, eliminate production risks and maintain company focus. However, we cannot be certain these customers will continue to purchase our products in the future. Increased levels of production insourcing by these customers could result from a number of factors, such as shifts in our customers’ business strategies, acquisition by a customer of another transmission or propulsion solution manufacturer, the inability of third-party suppliers to meet specifications and the emergence of low-cost production opportunities in foreign countries. As a result, these OEMs may use products produced internally or by another manufacturer and no longer choose to purchase products from us. A significant reduction in the level of external sourcing by our OEM customers could significantly impact our net sales and cash flows and, accordingly, have a material adverse effect on our business, results of operations and financial condition.

Our financial condition and results of operations have been and may continue to be materially adversely affected by the coronavirus pandemic.

The global spread of the novel strain of coronavirus (COVID-19) that has been declared a pandemic by the World Health Organization and the preventative measures taken to contain or mitigate the outbreak have caused, and are continuing to cause, significant volatility and uncertainty and economic disruptions. Governments around the world continue to implement measures to contain or mitigate the spread of the virus, including vaccine and testing mandates, quarantines, “shelter in place” and “stay at home” orders, travel restrictions, business curtailments and other measures, due to the ongoing pandemic. While we continue to operate our plants consistent with applicable government guidelines, we may experience production shutdowns or slowdowns at our manufacturing facilities as a result of government orders, our inability to obtain component parts from suppliers,

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labor shortages or decreased customer production schedules. In addition, many of our suppliers and customers have experienced, and may continue to experience, production slowdowns and/or shutdowns, as a result of government orders and supply chain, raw material, labor and logistics constraints, which have impacted, and may continue to impact, our business, sales and results of operations.

The effects of the COVID-19 pandemic on the global economy had a material impact on demand for our products and our results of operations during 2021. While we continued to experience a recovery in demand for our products during 2021, ongoing supply chain, labor, raw material, freight and logistics constraints have negatively impacted, and may continue to negatively impact, the sales of our products, expenses and our results of operations. In addition, future pandemic-related impacts on the global economy, including inflation, may continue to adversely impact our business and results of operations. The extent to which the COVID-19 pandemic may continue to adversely impact our business depends on future developments, which are highly uncertain and unpredictable, including the severity and duration of the outbreak, emerging variants of the virus that may be more contagious than current variants and the effectiveness of actions taken globally to contain or mitigate its effects, including the availability, pace of distribution, acceptance of and effectiveness of vaccines. In addition, vaccine or testing mandates adopted by the U.S. or other governments in order to combat the pandemic may result in additional labor shortages and/or increased costs for us or our suppliers and customers that may have a material impact on our business. Any future financial impact cannot be estimated reasonably at this time, but may materially adversely affect our business, supply chain, sales, results of operations, financial condition and cash flows. Even after the COVID-19 pandemic has subsided, we may experience materially adverse impacts to our business due to any resulting economic recession or depression that may continue to impact customer demand and the financial instability or operating viability of our suppliers and customers. Additionally, concerns over the economic impact of COVID-19 have caused extreme volatility in financial and other capital markets which may adversely impact our ability to access capital markets.

Increases in cost, disruption of supply or shortage of raw materials or components used in our products could harm our business and profitability.

Our products contain various raw materials, including corrosion-resistant steel, non-ferrous metals such as aluminum and nickel, and precious metals such as platinum and palladium. We use raw materials directly in manufacturing and in components that we purchase from our suppliers. We generally purchase components with significant raw material content on the open market. The prices for and availability of these raw materials fluctuate depending on market conditions. Volatility in the prices of raw materials such as steel, aluminum and nickel could increase the cost of manufacturing our products. Additionally, our suppliers are also subject to fluctuations in the prices of raw materials and may attempt to pass all or a portion of such increases on to us. In the event they are successful in doing so, our margins would decline. Temporary industry-wide shortages of raw materials have occurred in 2021, which has led to increased raw material price volatility and cost increases which could continue into 2022. We may not be able to pass on these costs to our customers, and this could have a material adverse effect on our business, results of operations and financial condition. Even in the event that increased costs can be passed through to customers, our gross margin percentages would decline as the recovery of these costs from customers generally lags six to twelve months.

In 2021, approximately 75% of our total spending on components was sourced from approximately 40 suppliers, many of which are the single source for such components. All of the suppliers from which we purchase materials and components used in our business are fully validated suppliers, meaning the suppliers’ manufacturing processes and inputs have been validated under a production part approval process (“PPAP”). Furthermore, there are only a limited number of suppliers for certain of the materials used in our business, such as corrosion-resistant steel. As a result, our business is subject to the risk of additional price fluctuations and periodic delays in the delivery of our materials or components if supplies from a validated supplier are interrupted and a new supplier, if

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one is available, must be validated or materials and components must be purchased from a supplier without a completed PPAP, which could increase our risk of purchasing non-conforming components. Any such price fluctuations or delays, if significant, could harm our profitability or operations. In addition, the loss of a supplier could result in significant material cost increases or reduce our production capacity. We have experienced, and expect to continue to experience, delays in the availability and receipt of raw materials and component parts as a result of the COVID-19 pandemic, some of which may materially impact our ability to meet customer demand. We also cannot guarantee we will be able to maintain favorable arrangements and relationships with these suppliers. An increase in the cost or a sustained interruption in the supply or shortage of some of these raw materials or components that may be caused by a deterioration of our relationships with suppliers or by events such as natural disasters and extreme weather events which may increase in frequency and intensity as a result of climate change, power outages, labor strikes and public health crisis such as pandemics and epidemics or the like could negatively impact our business, results of operations and financial condition. Although we have agreements with many of our customers that we will pass such price increases through to them, such contracts may be canceled by our customers and/or we may not be able to recoup the costs of such price increases. Additionally, if we are unable to continue to purchase our required quantities of raw materials on commercially reasonable terms, or at all, if we are unable to maintain or enter into purchasing contracts for commodities, or if delivery of materials or component parts from suppliers is delayed or non-conforming, our operations could be disrupted, we may not be able to meet customer demand, and our profitability and our financial results may be materially impacted.

Labor cost inflation, employee attraction and retention or labor unrest could have an adverse effect on our business, results of operations and financial condition.

As of December 31, 2021, approximately 46% of our U.S. employees, representing approximately 42% of our total employees, were represented by the UAW and are subject to a collective bargaining agreement. Our current collective bargaining agreement with UAW Local 933 is effective through November 2023. In addition to our unionized work force, many of our direct and indirect customers and vendors have unionized work forces. Strikes, work stoppages or slowdowns experienced by these customers or vendors or their other suppliers could result in slowdowns or closings of assembly plants that use our products or supply materials for use in the production of our products. Organizations responsible for shipping our products may also be impacted by strikes. Any interruption in the delivery of our products could reduce demand for our products and could have a material adverse effect on us.

In general, we consider our labor relations with all of our employees to be good. However, in the future we may be subject to labor unrest. If strikes, work stoppages or lock-outs at our facilities or at the facilities of our vendors or customers occur or continue for a long period of time, our business, results of operations and financial condition may be materially adversely affected.

Our success depends on our ability to identify, recruit and retain highly skilled, qualified personnel, and there is currently increased competition for talent. We have experienced labor shortages and wage inflation amid low levels of unemployment and workforce availability. As a result, we may not be able to attract and retain qualified personnel, which may impact our ability to manufacture, design and develop our propulsion solutions and to compete effectively. In addition, we may continue to experience increased labor costs, which may impact our results of operations.

Prolonged inflation could result in higher costs and decreased margins and earnings.

Recent inflationary pressures have resulted in increased raw material, labor, energy, freight and logistics expenses and other costs, which, if they continue for a prolonged period, may adversely affect our results of operations. If our costs are subject to continuing significant inflationary pressures, we may not be able to fully offset such higher costs through price increases. Our inability to do so could harm our results of operation.

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Volatility in and disruption to the global economic environment and changes in the regulatory and business environments in which we operate may have a material adverse effect on our business, results of operations and financial condition.

The commercial vehicle industry as a whole has been more adversely affected by volatile economic conditions than many other industries, as the purchase or replacement of commercial vehicles, which are durable items, can be deferred for many reasons, including reduced spending by end users. Future changes in the regulatory and business environments in which we operate, including increased trade protectionism and tariffs, may adversely affect our ability to sell our products or source materials needed to manufacture our products. Furthermore, financial instability or bankruptcy at any of our suppliers or customers could disrupt our ability to manufacture our products and impair our ability to collect receivables, any or all of which may have a material adverse effect on our business, results of operations and financial condition. In addition, some of our customers and suppliers may experience serious cash flow problems and, thus, may find it difficult to obtain financing, if financing is available at all. As a result, our customers’ need for and ability to purchase our products or services may decrease, and our suppliers may increase their prices, reduce their output or change their terms of sale. Any inability of customers to pay us for our products and services, or any demands by suppliers for different payment terms, may materially and adversely affect our results of operations and financial condition. Furthermore, our suppliers may not be successful in generating sufficient sales or securing alternate financing arrangements, and therefore may no longer be able to supply goods and services to us. In that event, we would need to find alternate sources for these goods and services, and there is no assurance we would be able to find such alternate sources on favorable terms, if at all. Any such disruption in our supply chain could adversely affect our ability to manufacture and deliver our products on a timely basis, and thereby affect our results of operations.

Certain of our end users operate in highly cyclical industries, which can result in uncertainty and significantly impact the demand for our products, which could have a material adverse effect on our business, results of operations and financial condition.

Some of the markets in which we operate, including energy, mining, construction, distribution and motorhomes, exhibit a high degree of cyclicality. Decisions to purchase our products are largely a result of the performance of these and other industries we serve. If demand for output in these industries decreases, the demand for our products will likely decrease. Demand in these industries is impacted by numerous factors including prices of commodities, rates of infrastructure spending, housing starts, real estate equity values, interest rates, consumer spending, fuel costs, energy demands, municipal spending, commercial construction and global pandemics, among others. Increases or decreases in these variables globally may significantly impact the demand for our products, which could have a material adverse effect on our business, results of operations and financial condition. If we are unable to accurately predict demand, we may be unable to meet our customers’ needs, resulting in the loss of potential sales, or we may manufacture excess products, resulting in increased inventories and overcapacity in our production facilities, increasing our unit production cost and decreasing our operating margins.

Our sales are concentrated among our top five OEM customers and the loss or consolidation of any one of these customers or the discontinuation of particular vehicle models for which we are a significant supplier could reduce our net sales and have a material adverse effect on our results of operations and financial condition.

We have in the past and may in the future derive a significant portion of our net sales from a relatively limited number of OEM customers. For the years ended December 31, 2021, 2020 and 2019, our top five OEM customers accounted for approximately 52%, 53% and 54% of our net sales, respectively. Our top three customers, Daimler AG, PACCAR Inc. and Traton SE (includes Navistar International Corporation as of December 31, 2021) accounted for approximately 20%, 10% and 10%, respectively, of our net sales during 2021. The loss of, or consolidation of, any one of these customers, or a significant decrease in business from, one or more of these customers could harm

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our business. In addition, the discontinuation of particular vehicle models for which we are a significant supplier could reduce our net sales and have a material adverse effect on our results of operations.

Our sales to the Defense end market are to government entities and contractors for the U.S. and foreign governments, and the loss of a significant number of our contracts, or budgetary declines or future reductions or changes in spending by the U.S. or foreign governments could have a material adverse effect on our results of operations and financial condition.

Our net sales to the Defense end market are derived from contracts (revenue arrangements) with agencies of, and prime system contractors for, the U.S. government and foreign governments. If a significant number of our Defense contracts and subcontracts are simultaneously delayed or cancelled for budgetary, performance or other reasons, it would have a material adverse effect on our results of operations and financial condition. Approximately 8%, or $186 million, of our net sales for the year ended December 31, 2021 were from our Defense end market.

Our future financial results may be adversely affected by:

Our brand and reputation are dependent on the continued participation and level of service of our numerous independent distributors and dealers.

We work with a network of approximately 1,400 independent distributors and dealers that provide post-sale service, service parts and support equipment. Because we depend on the pull-through demand generated by end users for our products, any actions by the independent distributors or dealers, which are not in our control, may harm our reputation and damage the brand loyalty among our customer base. In the event that we are not able to maintain our brand reputation because of the actions of our independent distributors and dealers, we may face difficulty in maintaining our pricing positions with respect to some of our products or have reduced demand for our products, which could negatively impact our business, results of operations and financial condition. In addition, if a significant number of independent dealers were to terminate their contracts, it could adversely impact our business, results of operations and financial condition.

We are subject to cybersecurity risks to operational systems, security systems, or infrastructure owned by Allison or third-party vendors or suppliers.

We are at risk for interruptions, outages, and breaches of: (i) operational systems, including business, financial, accounting, product development, data processing, or manufacturing processes, owned by us or our third-party vendors or suppliers; (ii) facility security systems, owned by us or our third-party vendors or suppliers; and/or (iii) vehicle propulsion control modules or other in-product technology, owned by us or our third-party vendors or suppliers. Such cyber incidents could materially disrupt operational systems; result in loss of intellectual property, trade secrets or other proprietary or competitively sensitive information; compromise personally identifiable information of employees, customers, suppliers, or others; jeopardize the security of our facilities; and/or affect the performance of vehicle propulsion control modules or other in-product technology. A cyber incident could be caused by malicious third parties using sophisticated, targeted methods to circumvent firewalls, encryption, and other security defenses, including hacking, fraud, trickery, or other forms of deception. The techniques used by third

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parties change frequently and may be difficult to detect for long periods of time. A significant cyber incident could impact production capability, harm our reputation and/or subject us to regulatory actions or litigation, any of which could materially affect our business, results of operations and financial condition. While we utilize a number of measures to prevent, detect and mitigate these threats, including employee education, monitoring of networks and systems, and maintenance of backup and protective systems, there is no guarantee such efforts will be successful in preventing a cyber incident.

In the event of a catastrophic loss of our key manufacturing facility, our business would be adversely affected.

While we manufacture our products in several facilities and maintain insurance covering our facilities, including business interruption insurance, a catastrophic loss of the use of all or a portion of one of our manufacturing facilities due to accident, labor issues, weather conditions, acts of war, political unrest, terrorist activity, natural disaster or extreme weather events, which may increase in frequency and intensity as a result of climate change, public health crisis, such as pandemics and epidemics or otherwise, whether short- or long-term, would have a material adverse effect on our business, results of operations and financial condition. Our most significant concentration of manufacturing is around our corporate headquarters in Indianapolis, Indiana, where we produce approximately 90% of our transmissions. In addition to our Indianapolis manufacturing facilities, we currently operate manufacturing facilities for our fully electric propulsion solutions in Auburn Hills, Michigan, for our transmissions in both Szentgotthard, Hungary and Chennai, India and for our aluminum die cast components in Lewisburg, Tennessee. In the event of a disruption at the Indianapolis facilities, our other facilities may not be adequately equipped to operate at a level sufficient to compensate for the volume of production at the Indianapolis facility due to their size and the fact that they have not yet been tested for such significant increases in production volume.

Strategic Risks

Our success depends on research and development efforts, and we may not be successful in developing or introducing new products and technologies and responding to customer needs.

Our success depends on our ability to develop or introduce new products and technologies and improve the efficiency and performance of our current products, and we invest significant resources in research and development in order to do so. We currently have enhancements to our existing products and technologies and new products and technologies under development, including electric hybrid and fully electric propulsion solutions, for planned introduction into certain end markets. The development of new products and technologies is difficult, time-consuming and costly and the timetable for commercial release is uncertain. Not all of our new product launches have been successful, and we may not be successful in the future in introducing other new products and responding to customer needs. In addition, it often takes significant time, in some cases multiple fleet buy cycles, before customers gain experience with new products and technologies and those new products and technologies become widely-accepted by the market, if at all. Given the early stages of development of some of these new products and technologies, there can be no guarantee of future market acceptance and investment returns with respect to these products. In addition, the increased adoption of electric propulsion solutions could result in lower demand for our fully automatic transmissions and, over time, the demand for related service parts and support equipment, which would impact our margins. If we do not adequately anticipate the changing needs of our customers by keeping pace with improvements and changes in vehicle propulsion technology and developing and introducing new and effective products and technologies on a timely basis, or if the products and technologies we develop do not become market-leading, our competitive position and prospects could be harmed. If our competitors are able to respond to changing market demands and adopt new technologies more quickly than we do, demand for our products could decline, our competitive position could be harmed, our future research and development

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activities may be constrained due to intellectual property rights of others, licenses for technologies that would enable us to keep pace with our competitors may not be available on commercially reasonable terms if at all and we may not be able to recoup a return on our development investments. Moreover, changing customer demands as well as evolving regulatory, safety and environmental standards could require us to adapt our products and technologies to address such changes. As a result, in the future we may experience delays in the introduction of some or all of our new products or modifications or enhancements of existing products. Furthermore, there may be production delays due to unanticipated technological setbacks, which may, in turn, delay the release of new products to our end users. If increased regulatory or environmental standards cause the rate of adoption of new technologies, including electric vehicles for the medium- and heavy-duty commercial market, to occur at a pace that is faster than we are anticipating, we may not have products available to meet that accelerated timeframe. If we experience significant delays or increased costs in the production, launch or acceptance of our products and technologies, our net sales and results of operations may be materially adversely affected.

Our long-term growth prospects and results of operations may be impaired if the rate of adoption of fully automatic transmissions in commercial vehicles outside North America does not increase.

Our long-term growth strategy depends in part on an increased rate of automaticity outside North America. As part of that strategy, we have established manufacturing facilities in India and Hungary. We have also dedicated significant human resources to serve markets where we anticipate increased adoption of automaticity, including China, India, Brazil and Russia. However, manual transmissions remain the market leader outside North America and there can be no assurance that adoption of automatic transmissions will increase. Factors potentially impacting adoption of automatic transmissions outside of North America include the large existing installed base of manual transmissions, customer preferences for manual transmissions, commercial vehicle OEM vertical integration into manual transmission and AMT manufacturing, increased competition from AMTs, electric propulsion solutions, and other alternative transmission and propulsion solution technologies and failure to further develop the Allison brand. If the rate of adoption of fully automatic transmissions does not increase as we have anticipated, our long-term growth prospects and results of operations may be impaired.

Our international operations, in particular our emerging markets, are subject to various risks which could have a material adverse effect on our business, results of operations and financial condition.

Our business is subject to certain risks associated with doing business internationally, particularly in emerging markets. Outside-North America net sales represented approximately 24% of our net sales for 2021. Most of our operations are in the U.S., but we also have manufacturing and customization facilities in India and Hungary with a services agreement with Stellantis NV and customization capability in Brazil, The Netherlands, China and Japan. Further, we intend to continue to pursue growth opportunities for our business in a variety of business environments outside the U.S., which could exacerbate the risks set forth below. Our international operations are subject to, without limitation, the following risks:

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Any one of these factors could materially adversely affect our sales of products or services to international customers or harm our reputation, which could have a material adverse effect on our business, results of operations and financial condition.

We may not be able to identify or consummate acquisitions or partnerships or achieve expected benefits from or effectively integrate acquisitions or partnerships, which could harm our growth.

From time to time we evaluate selective acquisitions, partnerships and strategic investments. Potential and completed acquisitions and partnerships involve many risks that could have an adverse effect on our business, financial condition or results of operations, including:

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We may also face liability with respect to acquired businesses for violations of environmental or other laws occurring prior to the date of our acquisition, and some or all of these liabilities may not be covered by environmental or other insurance secured to mitigate the risk or by indemnification from the sellers from which we acquired these businesses. We could also incur significant costs, including, but not limited to, remediation costs, natural resources damages, civil or criminal fines and sanctions and third-party claims, as a result of past or future violations of, or liabilities associated with, environmental or other laws.

We cannot offer any assurance that we will be able to consummate any future acquisitions, strategic investments, partnerships or other business combinations. If we are unable to identify suitable acquisition candidates or to consummate and successfully integrate our recent and any future acquisitions, our business and results of operations may be adversely affected as a result.

Legal and Regulatory Risks

Any events that impact our brand name, including if the products we manufacture or distribute are found to be defective, could have an adverse effect on our reputation, cause us to incur significant costs and negatively impact our business, results of operations and financial condition.

We face exposure to product liability claims in the event that the use of our products has, or is alleged to have, resulted in injury, death or other adverse effects. We currently maintain product liability insurance coverage, but we cannot be assured that we will be able to obtain such insurance on acceptable terms in the future, if at all, or that any such insurance will provide adequate coverage against potential claims. Product liability claims can be expensive to defend and can divert the attention of management and other personnel for long periods of time, regardless of the ultimate outcome. An unsuccessful product liability defense could have a material adverse effect on our business, results of operation, financial condition or prospects. If one of our products is determined to be defective, we may face substantial warranty costs and may be responsible for significant costs associated with a product recall or a redesign. We have had defect and warranty issues associated with certain of our products in the past, and we cannot give assurance similar product defects will not occur in the future. See "NOTE 10. Product Warranty Liabilities” of Notes to Consolidated Financial Statements included in Part II, Item 8. of this Annual Report on Form 10-K for additional details regarding these warranty issues.

Furthermore, our business depends on the strong brand reputation we believe we have developed. In addition to the risk of defective products, we also face significant risks in our efforts to penetrate new markets, where we have limited brand recognition. We also rely on our reputation with end users of our products to specify our products when purchasing new vehicles from our OEM customers. In the event we are not able to maintain or enhance our brand in these new markets or our reputation is damaged in our existing markets as a result of product defects or recalls, we may face difficulty in maintaining our pricing positions with respect to some of our products or experience reduced demand for our products, which could negatively impact our business, results of operations and financial condition.

Additionally, we license the “Allison Transmission” name and certain related trademarks to third parties. If any third party uses the trade name “Allison Transmission” in ways that adversely affect such trade name or trademark, our reputation could suffer damage, which in turn could have a material adverse effect on our business, results of operations and financial condition.

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Many of the key patents and unpatented technology we use in our business are licensed to us, not owned by us, and our ability to use and enforce such patents and technology is restricted by the terms of the license.

Protecting our intellectual property rights is critical to our ability to compete and succeed as a company. General Motors Company (“GM”) has granted us an irrevocable, perpetual, royalty-free, worldwide license under a large number of U.S. and foreign patents and patent applications, as well as certain unpatented technology and know-how, to design, develop, manufacture, use and sell fully automatic transmissions and electric hybrid propulsion solution for use in certain vocational vehicles, defense vehicles and off-road products. With respect to the bulk of the intellectual property licensed to us, our license is exclusive with respect to the design, development, manufacture, use and sale of fully automatic transmissions and electric hybrid propulsion solution in vocational vehicles above certain weight rating thresholds, certain defense vehicles and certain off-road products. It is non-exclusive with respect to certain other products that are within the scope of the licensed patents or to which the licensed technology can be applied. GM continues to own such patents and technology, and GM has the right, in the first instance, to control the maintenance, enforcement and defense of such patents and the prosecution of the licensed patent applications. In addition, our ability to sublicense our rights is limited.

We rely on unpatented technology, which exposes us to certain risks.

We currently do, and may continue in the future to, rely on unpatented proprietary technology. In such regard, we cannot be assured that any of our applications for protection of our intellectual property rights will be approved or that others will not infringe or challenge our intellectual property rights. It is possible our competitors will independently develop the same or similar technology or otherwise obtain access to our unpatented technology.

Although we believe the loss or expiration of any single patent would not have a material effect on our business, results of operations or financial position, there can be no assurance that any one, or more, of the patents or any other intellectual property owned by or licensed to us, will not be challenged, invalidated or circumvented by third parties. In fact, a number of the patents licensed to us are set to expire in the next few years. When a patent expires, the inventions it discloses can be used freely by others. Thus, the competitive advantage that we gain from the patents licensed to us will decrease over time, and a greater burden will be placed on our own research and development and licensing efforts to develop and otherwise acquire technologies to keep pace with improvements of transmission-related technology in the marketplace. We enter into confidentiality and invention assignment agreements with employees, and into non-disclosure agreements with suppliers and appropriate customers so as to limit access to and disclosure of our proprietary information. We cannot be assured that these measures will provide meaningful protection for our trade secrets, know-how or other proprietary information in the event of any unauthorized use, misappropriation or disclosure. If we are unable to maintain the proprietary nature of our technologies, our ability to sustain margins on some or all of our products may be affected, which could reduce our sales and profitability. Moreover, the protection provided for our intellectual property by the laws and courts of foreign nations may not be as advantageous to us as the protection available under U.S. law.

Environmental, health and safety laws and regulations may impose significant compliance costs and liabilities on us.

Our manufacturing operations are subject to many environmental, health and safety laws and regulations governing emissions to air, discharges to water, the generation, handling and disposal of waste and the cleanup of contaminated properties. Compliance with these laws and regulations is costly. We have incurred and expect to continue to incur significant costs to maintain or achieve compliance with applicable environmental, health and safety laws and regulations. Moreover, regulatory bodies are increasingly adopting regulations that target limiting greenhouse gases and combatting climate change, which may impact our ability to sell our current products or require us to develop new products or technologies. If these environmental, health and safety laws and regulations that impact our operations or products become more stringent or expand to include a larger portion of our products

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or our customer’s products in the future, we could incur additional costs in order to ensure that our business and products comply with such regulations. In addition, we may not be successful in developing products or technologies that comply with, or the vehicle or customer OEMs to which we sell our products may choose not to comply with, such laws and regulations, which could impact our ability to sell our products in certain locations, negatively impact our business and result in a loss of market share. Furthermore, if our products that are already placed in service are found to be non-compliant with certain laws, regulations and certifications, we may incur additional costs and fines. We cannot assure that we are in full compliance with all environmental, health and safety laws and regulations. Our failure to comply with applicable environmental, health and safety laws and regulations and permit requirements could result in civil or criminal fines, penalties or enforcement actions, third-party claims for property damage and personal injury, requirements to clean up property or to pay for the costs of cleanup or regulatory or judicial orders enjoining or curtailing operations or requiring corrective measures, including the installation of pollution control equipment or remedial actions. Our failure to comply could also result in our failure to secure adequate insurance for our business, resulting in significant exposure, diminished ability to hedge our risks and material modifications of our business operations.

We may be subject to liability as a potentially responsible party under the Comprehensive Environmental Response, Compensation and Liability Act and similar state or foreign laws for contaminated properties that we currently own, lease or operate or that we or our predecessors have previously owned, leased or operated, and sites to which we or our predecessors sent hazardous substances. Such liability may be joint and several so that we may be liable for more than our share of any contamination, and any such liability may be determined without regard to causation or knowledge of contamination. We or our predecessors have been named potentially responsible parties at contaminated sites from time to time.

We manage the remediation of historical soil and groundwater contamination at our Indianapolis, Indiana facilities under an Agreed Order of Consent with the EPA. See Part II, Item 8., "NOTE 18. Commitments and Contingencies” of this Annual Report on Form 10-K. There can be no assurances that future environmental remediation obligations will not have a material adverse effect on our results of operations and financial condition. In addition, we occasionally evaluate alternatives with respect to our facilities, including possible dispositions or closings. Investigations undertaken in connection with these activities may lead to discoveries of contamination that must be remediated, and closings of facilities may trigger remediation requirements that are not applicable to operating facilities. We may also face lawsuits brought by third parties that either allege property damage or personal injury as a result of, or seek reimbursement for costs associated with, such contamination.

Our business and financial results may be adversely affected by U.S. government contracting risks.

We are subject to various laws and regulations applicable to parties doing business with the U.S. government, including laws and regulations governing performance of U.S. government contracts, the use and treatment of U.S. government furnished property and the nature of materials used in our products. We may be unilaterally suspended or barred from conducting business with the U.S. government, or become subject to fines or other sanctions if we are found to have violated such laws or regulations. As a result of the need to comply with these laws and regulations, we are subject to increased risks of governmental investigations, civil fraud actions, criminal prosecutions, whistleblower lawsuits and other enforcement actions. The laws and regulations to which we are subject include, but are not limited to, Export Administration Regulations, the Federal Acquisition Regulation, International Traffic in Arms Regulations and regulations from the Bureau of Alcohol, Tobacco, Firearms and Explosives and the FCPA.

U.S. government contracts are subject to modification, curtailment or termination by the U.S. government without prior written notice, either for convenience or for default as a result of our failure to perform under the applicable contract. If terminated by the U.S. government as a result of our default, we could be liable for additional costs the U.S. government incurs in acquiring undelivered goods or services from another source and any other

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damages it suffers. Additionally, we cannot assign prime U.S. government contracts without the prior consent of the U.S. government contracting officer, and we are required to register with the Central Contractor Registration Database. Furthermore, the U.S. government periodically audits our governmental contract costs, which could result in fines, penalties or adjustment of costs and prices under the contracts. The result of, or expiration of the statute of limitations for, such audits could have an impact on reported liabilities, net income and cash flow from operations.

Provisions of our amended and restated certificate of incorporation and amended and restated bylaws and Delaware law might discourage, delay or prevent a change of control of our company or changes in our management and, as a result, depress the trading price of our common stock.

Our amended and restated certificate of incorporation and amended and restated bylaws contain provisions that could discourage, delay or prevent a change in control of our company or changes in our management that the stockholders of our company may deem advantageous. These provisions:

These anti-takeover defenses could discourage, delay or prevent a transaction involving a change in control of our company that our stockholders may believe to be in their best interests. These provisions could also discourage proxy contests and make it more difficult for our stockholders to elect directors of their choosing and cause us to take corporate actions other than those they desire.

Risks Related to Our Indebtedness and Financial Risks

Our indebtedness could adversely affect our financial health, restrict our activities and affect our ability to meet our obligations.

As of December 31, 2021, we had total indebtedness of $2,531 million and we would have been able to borrow an additional $645 million, net of $5 million of outstanding letters of credit, under Allison Transmission Inc.’s (“ATI”), our wholly-owned subsidiary, revolving credit facility with commitments in the amount of $650 million due September 2025 (“Revolving Credit Facility”). As of December 31, 2021, we had no outstanding borrowings against the Revolving Credit Facility. At December 31, 2021, $631 million of our total indebtedness was associated with ATI’s term loan facility due March 2026 (“Term Loan”, and together with the Revolving Credit Facility, the “Senior Secured Credit Facility”), $400 million of our total indebtedness was associated with ATI’s 4.75% Senior Notes due October 2027 (“4.75% Senior Notes”), $500 million of our total indebtedness was associated with ATI’s 5.875% Senior Notes due June 2029 (“5.875% Senior Notes”) and $1,000 million of our total indebtedness was associated with ATI’s 3.75% Senior Notes due January 2031 (“3.75% Senior Notes”, and together with the 4.75% Senior Notes and 5.875% Senior Notes, the “Senior Notes”). For a complete description of the terms of the Senior Secured Credit

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Facility and the Senior Notes, please see "NOTE 8. Debt” in Part II, Item 8., of this Annual Report on Form 10-K for additional information of this Annual Report on Form 10-K.

Our indebtedness could have important consequences. For example, it could:

In addition, the Revolving Credit Facility contains a maximum total senior secured leverage ratio. The Senior Secured Credit Facility and the indentures governing the Senior Notes also contain other negative and affirmative covenants that will limit our ability to engage in activities that may be in our long-term best interests. Our failure to comply with any of the covenants could result in an event of default which, if not cured or waived, could result in the acceleration of all of our indebtedness.

To service our indebtedness, we will require a significant amount of cash, and our ability to generate cash depends on many factors beyond our control.

Our ability to make cash payments on our indebtedness and to fund planned capital expenditures will depend on our ability to generate significant operating cash flow in the future. This, to a significant extent, is subject to general economic, financial, competitive, legislative, regulatory and other factors that are beyond our control.

We cannot ensure that our business will generate sufficient cash flow from operations or that future borrowings will be available to us under the Senior Secured Credit Facility in an amount sufficient to enable us to pay our indebtedness or to fund our other liquidity needs. In such circumstances, we may need to refinance all or a portion of our indebtedness on or before maturity. We cannot ensure that we will be able to refinance any of our indebtedness on commercially reasonable terms or at all. If we cannot service our indebtedness, we may have to take actions such as selling assets, seeking additional equity or reducing or delaying capital expenditures, strategic acquisitions, investments and alliances. We cannot ensure that any such actions, if necessary, could be effected on commercially reasonable terms or at all.

If we fail to pay principal, premium, if any, and interest on our indebtedness or to otherwise comply with the covenants in the instruments governing our indebtedness, we may be forced into bankruptcy or liquidation by our lenders.

If we are unable to generate sufficient cash flow or are otherwise unable to obtain funds necessary to meet required payments of principal, premium, if any, and interest on our indebtedness, or if we otherwise fail to comply with the various covenants in the instruments governing our indebtedness, we could be in default under the terms of the agreements governing such indebtedness. In the event of such default, the holders of such indebtedness could elect to declare all the funds borrowed thereunder to be due and payable, together with accrued and unpaid interest, the lenders under the Senior Secured Credit Facility could elect to terminate their commitments thereunder,

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cease making further loans and institute foreclosure proceedings against our assets, and we could be forced into bankruptcy or liquidation. If our operating performance declines, we may in the future need to obtain waivers from the required lenders under the Senior Secured Credit Facility to avoid being in default. If we or any of our subsidiaries breach the covenants under the Senior Secured Credit Facility and seek a waiver, we may not be able to obtain a waiver from the required lenders. If this occurs, we would be in default under the Senior Secured Credit Facility, the lenders could exercise their rights, as described above, and we could be forced into bankruptcy or liquidation.

Despite current indebtedness levels, we and our subsidiaries may still be able to incur additional indebtedness, which could further exacerbate the risks associated with our substantial financial leverage.

We and our subsidiaries may be able to incur additional indebtedness in the future because the terms of our indebtedness do not fully prohibit us or our subsidiaries from doing so. Subject to covenant compliance and certain conditions, our indebtedness permits additional borrowing, including total borrowing up to $645 million under the Revolving Credit Facility, net of $5 million in letters of credit. If new debt is added to our current debt levels and our subsidiaries’ current debt levels, the related risks that we and they now face could intensify.

Our pension and other post-retirement benefits funding obligations could increase as a result of a variety of factors.

Our earnings may be positively or negatively impacted by the amount of income or expense recorded for our defined benefit pension plans and other post-retirement benefits (“OPEB”). Accounting principles generally accepted in the United States of America (“GAAP”) require that income or expense for defined benefit pension plans be calculated at the annual measurement date, or more frequently if certain events occur, using actuarial assumptions and calculations. These calculations reflect certain assumptions, the most significant of which relate to the capital markets, interest rates, health care inflation rates and other economic conditions. Changes in key economic indicators can change these assumptions. These assumptions, along with the actual value of assets at the measurement date, will impact the calculation of pension expense for the year. Although GAAP pension expense and pension contributions are not directly related, the key economic indicators that affect GAAP pension expense also affect the amount of cash that we would contribute to our defined benefit pension plans. Because the values of these defined benefit pension plans’ assets have fluctuated and will fluctuate in response to changing market conditions, the amount of gains or losses that will be recognized in subsequent periods, the impact on the funded status of the defined benefit pension plans and the future minimum required contributions, if any, could have a material adverse effect on our business, results of operations and financial condition. The magnitude of such impact cannot be determined with certainty at this time. However, the effect of a one percentage point decrease in the assumed discount rate would result in an increase in the December 31, 2021 defined benefit pension plans obligation of approximately $27 million. Likewise, a one percentage point decrease in the effective interest rate for determining defined benefit pension plans contributions would result in an increase in the minimum required contributions for 2022 of approximately $2 million. Similarly, a one percentage point decrease in the assumed discount rate would result in an increase in the December 31, 2021 OPEB obligation of approximately $15 million. As of December 31, 2021, the unfunded status of our defined benefit pension plans was $7 million and the unfunded status of our OPEB plan was $102 million.

An impairment in the carrying value of goodwill, other intangible assets or long-lived assets could negatively affect our consolidated results of operations and net worth.

Pursuant to GAAP, we are required to assess our goodwill and indefinite-lived intangible assets to determine if they are impaired on an annual basis, or more often if events or changes in circumstances indicate that impairment may have occurred. Intangible assets with finite lives are amortized over the useful life and are reviewed for impairment on triggering events such as events or changes in circumstances indicating that an impairment may

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have occurred. If the testing performed indicates that impairment has occurred, we are required to record a non-cash impairment charge for the difference between the carrying value of the goodwill and the implied fair value of the goodwill or the carrying value of the intangible assets and the fair value of the intangible assets in the period the determination is made. Disruptions to our business, end market conditions, protracted economic weakness, unsuccessful development of product and unexpected significant declines in operating results may result in charges for goodwill and other asset impairments. See "NOTE 2. Summary of Significant Accounting Policies” and "NOTE 6. Goodwill and Other Intangible Assets” of Notes to Consolidated Financial Statements included in Part II, Item 8. of this Annual Report on Form 10-K for additional details.

The carrying value of long-lived assets is evaluated whenever events or circumstances indicate that the carrying value of a long-lived asset may not be recoverable. Events or circumstances that would result in an impairment review primarily include a significant change in the use of an asset, a significant change in the projected future cash flows generated by an asset or the planned sale or disposal of an asset. The asset would be considered impaired when there is no future use planned for the asset or the future net undiscounted cash flows generated by the asset or asset group are less than its carrying value. An impairment loss would be recognized based on the amount by which the carrying value exceeds fair value and could have a material adverse effect on the results of our operations. See "NOTE 2. Summary of Significant Accounting Policies” and "NOTE 5. Property, Plant and Equipment” of Notes to Consolidated Financial Statements included in Part II, Item 8. of this Annual Report on Form 10-K for additional details.

ITEM 1B. UNRESOLVED STAFF COMMENTS

None.

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ITEM 2. PROPERTIES

Our world headquarters, which we own, is located at One Allison Way, Indianapolis, Indiana 46222. As of December 31, 2021, we have approximately 20 manufacturing and certain other facilities in eight countries. The following table sets forth certain information regarding our significant facilities.

We believe all our facilities are suitable for their intended purpose, are being efficiently utilized and provide adequate capacity to meet demand for the next several years. The table above does not include sales offices located in various countries.

ITEM 3. LEGAL PROCEEDINGS

We are subject to various contingencies, including routine legal proceedings and claims arising out of the normal course of business. These proceedings primarily involve commercial claims, product liability claims, personal injury claims and workers’ compensation claims. The outcome of these lawsuits, legal proceedings and claims cannot be predicted with certainty. Nevertheless, we believe the outcome of any of these currently existing proceedings, even if determined adversely, would not have a material adverse effect on our financial condition or results of operations. See also "NOTE 18. Commitments and Contingencies” in Part II, Item 8., of this Annual Report on Form 10-K.

ITEM 4. MINE SAFETY DISCLOSURES

Not applicable.

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PART II.

ITEM 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

Market Information

Our common stock is listed on the NYSE under the symbol “ALSN.”

Holders

As of February 4, 2022, there were approximately 63,474 stockholders of record of our common stock, which includes the actual number of holders registered on the books of the Company and holders of shares in “street name” or persons, partnerships, associations, corporations or other entities identified in security position listings maintained by depositories.

Unregistered Sales of Equity Securities

During the period covered by this Annual Report on Form 10-K, we did not offer or sell any equity securities that were not registered under the Securities Act of 1933, as amended (the “Securities Act”).

Issuer Purchases of Equity Securities

Our Board of Directors has authorized us to repurchase up to $3,000 million, in the aggregate, of our common stock pursuant to a stock repurchase program (the “Repurchase Program”). The terms of the Repurchase Program provide that we may repurchase shares of our common stock, from time to time depending on market conditions and corporate needs, in the open market or through privately negotiated transactions in accordance with Rule 10b-18 of the Exchange Act. The Repurchase Program does not have an expiration date.

The following table sets forth information related to our repurchase of our common stock on a monthly basis in the three months ended December 31, 2021:

Issuances Under Equity Compensation Plans

For information regarding the securities authorized for issuance under our equity compensation plans, see Part III, Item 12 of this Annual Report on Form 10-K.

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Comparative Stock Performance Graph

The information included under the heading “Comparative Stock Performance Graph” in this Item 5 of Part II of this Annual Report on Form 10-K shall not be deemed to be “soliciting material” or subject to Regulation 14A or 14C, shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act or the Exchange Act.

Set forth below is a graph comparing the total cumulative returns of ALSN, the S&P 500 Index and an index of peer companies selected by us. Our peer group includes Donaldson Company, Inc., Graco Inc., Roper Technologies, Inc., Gentex Corporation, Rockwell Automation, Inc. and Sensata Technologies Holding PLC. The graph assumes $100 was invested on December 31, 2016 in our common stock and each of the indices and that all dividends, if any, are reinvested.

ITEM 6. [RESERVED]

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ITEM 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

The following discussion contains forward-looking statements regarding industry trends, our expectations regarding our future performance, liquidity and capital resources and other non-historical statements that involve risks and uncertainties. Our actual results may differ materially from those discussed in or implied by the forward-looking statements as a result of various factors, including, without limitation, those set forth under Part I, Item 1A, “Risk Factors,” and other matters included elsewhere in this Annual Report on Form 10-K. The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our consolidated financial statements and the notes thereto included elsewhere in this Annual Report on Form 10-K.

This section of this Annual Report on Form 10-K generally discusses 2021 and 2020 items and year-over-year comparisons between 2021 and 2020. A detailed discussion of 2019 items and year-over-year comparisons between 2020 and 2019 that are not included in this Annual Report on Form 10-K can be found in “Management’s Discussion and Analysis of Financial Condition and Results of Operations” in Part II, Item 7 of our Annual Report on Form 10-K for the year ended December 31, 2020, as filed with the SEC on February 18, 2021.

Overview

We design and manufacture vehicle propulsion solutions, including commercial-duty on-highway, off-highway and defense fully automatic transmissions and electric hybrid and fully electric systems. The business was founded in 1915 and has been headquartered in Indianapolis, Indiana since inception. Allison is traded on the New York Stock Exchange under the symbol, “ALSN”.

We have approximately 3,400 employees. Although approximately 76% of revenues were generated in North America in 2021, we have a global presence by serving customers in Asia, Europe, South America and Africa. We serve customers through an independent network of approximately 1,400 independent distributor and dealer locations worldwide.

Trends Impacting Our Business

Throughout 2021, the COVID-19 pandemic continued to cause supply chain, labor and raw material constraints that created volatility in our business performance and impacted global markets and supply chains. As a result, we experienced, and expect to continue to experience, raw material and component part price inflation, increased freight and logistics costs and increased overtime expense as a result of labor shortages. In addition, despite increased customer demand our net sales for 2021 were negatively impacted as a result of our customers’ inability to secure components from the broader commercial vehicle supply base which resulted in reduced commercial vehicle build schedules. We expect that commercial vehicle build schedules will continue to be negatively impacted by the availability of components in 2022.

To limit the spread of COVID-19, governments continue to take various actions including the administration or mandate of vaccinations, travel bans and restrictions, quarantines, curfews, stay-at-home orders, social distancing guidelines and business shutdowns and closures. We are also continuing to take a variety of measures to promote the safety and security of our employees and to maintain operations with as minimal impact as possible to our stakeholders, and as a result, we have been able to continue our manufacturing operations and deliver our products to customers.

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Full Year 2021 and 2020 Net Sales by End Market (in millions)

North America On-Highway end market net sales were up 9% for the year ended December 31, 2021 compared to the year ended December 31, 2020, principally driven by the recovery in customer demand following the pandemic-related disruptions experienced in 2020 and price increases on certain products.

North America Off-Highway end market net sales were up $45 million for the year ended December 31, 2021 compared to the year ended December 31, 2020, principally driven by higher demand for hydraulic fracturing applications and price increases on certain products.

Defense end market net sales were up 2% for the year ended December 31, 2021 compared to the year ended December 31, 2020, principally driven by higher demand for Tracked vehicle applications and price increases on certain products, partially offset by lower Wheeled vehicle demand.

Outside North America On-Highway end market net sales were up 36% for the year ended December 31, 2021 compared to the year ended December 31, 2020, principally driven by the recovery in customer demand following the pandemic-related disruptions experienced in 2020, the execution of growth initiatives and price increases on certain products.

Outside North America Off-Highway end market net sales were up 36% for the year ended December 31, 2021 compared to the year ended December 31, 2020, principally driven by higher demand in the mining, energy and construction sectors and price increases on certain products.

Service Parts, Support Equipment and Other end market net sales were up 11% for the year ended December 31, 2021 compared to the year ended December 31, 2020, principally driven by higher demand for service parts and support equipment and price increases on certain products.

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Key Components of our Results of Operations

Net sales

We generate our net sales primarily from the sale of vehicle propulsion solutions, service and component parts, support equipment, defense kits, engineering services, royalties and extended transmission coverage to a wide array of OEMs, distributors and the U.S. government. Sales are recorded in accordance with the terms of the contract, net of provisions for customer allowances and other rebates.

Cost of sales

Our primary components of cost of sales are purchased parts, the overhead expense related to our manufacturing operations and direct labor associated with the manufacture and assembly of vehicle propulsion solutions and parts. For the year ended December 31, 2021, direct material costs were approximately 68%, overhead costs were approximately 24% and direct labor costs were approximately 8% of total cost of sales. We are subject to changes in our cost of sales caused by movements in underlying commodity prices. We seek to hedge against this risk by using LTAs. See Part II, Item 7A, “Quantitative and Qualitative Disclosures about Market Risk—Commodity Price Risk” included in this Annual Report on Form 10-K.

Selling, general and administrative

The principal components of our selling, general and administrative expenses are salaries and benefits for our office personnel, advertising and promotional expenses, product warranty expense, expenses relating to certain information technology systems and amortization of our intangible assets.

Engineering — research and development

We incur costs in connection with research and development programs that are expected to contribute to future earnings. Such costs are expensed as incurred.

Non-GAAP Financial Measures

We use Adjusted Earnings before Interest, Taxes, Depreciation, and Amortization (“EBITDA”) and Adjusted EBITDA as a percent of net sales to measure our operating profitability. We believe that Adjusted EBITDA and Adjusted EBITDA as a percent of net sales provide management, investors and creditors with useful measures of the operational results of our business and increase the period-to-period comparability of our operating profitability and comparability with other companies. Adjusted EBITDA as a percent of net sales is also used in the calculation of management’s incentive compensation program. The most directly comparable GAAP measure to Adjusted EBITDA and Adjusted EBITDA as a percent of net sales is Net income and Net income as a percent of net sales, respectively. Adjusted EBITDA is calculated as earnings before interest expense, net, income tax expense, amortization of intangible assets, depreciation of property, plant and equipment and other adjustments as defined by the Second Amended and Restated Credit Agreement dated as of March 29, 2019 as amended (the “Credit Agreement”) governing ATI's term loan facility due March 2026 (“Term Loan”). Adjusted EBITDA as a percent of net sales is calculated as Adjusted EBITDA divided by net sales.

We use Adjusted free cash flow to evaluate the amount of cash generated by our business that, after the capital investment needed to maintain and grow our business and certain mandatory debt service requirements, can be used for repayment of debt, stockholder distributions and strategic opportunities, including investing in our business. We believe that Adjusted free cash flow enhances the understanding of the cash flows of our business for management, investors and creditors. Adjusted free cash flow is also used in the calculation of management’s incentive compensation program. The most directly comparable GAAP measure to Adjusted free cash flow is Net cash provided by operating activities. Adjusted free cash flow is calculated as Net cash provided by operating activities, excluding non-recurring restructuring charges, after additions of long-lived assets.

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The following is a reconciliation of Net income and Net income as a percent of net sales to Adjusted EBITDA and Adjusted EBITDA as a percent of net sales and a reconciliation of Net cash provided by operating activities to Adjusted free cash flow: