ATI INC (ATI) Business

Item 1. Business

The Company

ATI Inc. is a Delaware corporation with its corporate headquarters located at 2021 McKinney Avenue, Suite 1100, Dallas, TX 75201, telephone number (800) 289-7454, Internet website address www.atimaterials.com. Our Internet website and content contained therein or connected thereto are not intended to incorporate into this Annual Report on Form 10-K. References to “ATI,” the “Company,” “the Registrant,” “we,” “our” and “us” and similar terms mean ATI Inc. and its subsidiaries, unless the context otherwise requires.

When used in this Annual Report on Form 10-K, unless the context otherwise requires or unless otherwise specified, any reference to “year” is to the Company’s fiscal year. The Company follows a 4-4-5 or 5-4-4 fiscal calendar, whereby each fiscal quarter consists of thirteen weeks grouped into two four-week months and one five-week month, and its fiscal year ends on the Sunday closest to December 31. Fiscal years 2025, 2024 and 2023 ended on December 28, 2025, December 29, 2024, and December 31, 2023, respectively. All fiscal years presented include 52 weeks of operations.

Our Business

ATI produces specialty materials, highly differentiated by our materials science expertise and advanced process technologies. Our mission is to solve the world’s challenges through materials science. Aerospace & defense, our largest end markets, represent approximately 68% of total sales, led by products for jet engines and airframes in addition to a wide range of defense applications. Additionally, we have a strong presence the specialty energy market and also serve customers in several other markets including conventional energy, medical, electronics and other industrial markets.

We operate in two business segments: High Performance Materials & Components (HPMC) and Advanced Alloys & Solutions (AA&S). HPMC produces a wide range of high performance materials, components, and advanced metallic powder alloys. These products are made from nickel-based alloys and superalloys, titanium and titanium-based alloys, and a variety of other specialty materials. HPMC’s capabilities range from cast/wrought and powder alloy development to production of highly engineered finished components, and 3D-printed aerospace products. The HPMC segment’s primary focus is on maximizing jet engine materials and components growth, with approximately 92% of its revenue derived from the aerospace & defense markets, including nearly 68% from products for commercial jet engines. Commercial aerospace products have been the main source of sales and EBITDA growth for HPMC over the last several years and are expected to continue to drive HPMC and overall ATI results in the future. HPMC has also experienced strong growth in defense products, with fiscal year 2025 sales growth of 24%. Sales of defense products comprise almost 11% of HPMC's total sales.

The AA&S segment produces nickel-based alloys, titanium and titanium-based alloys, and specialty alloys, including zirconium, hafnium, and niobium, in a variety of forms including plate, sheet, and strip products. AA&S focuses on high-value materials that are utilized in technically challenging and extreme environments, which require materials that can withstand extreme heat, radiation and corrosion. AA&S continued its focus of growing sales to the aerospace & defense end markets, with fiscal year 2025 sales to those markets increasing 15%. Aerospace & defense now comprises approximately 41% of AA&S total revenue. AA&S also serves customers across several other markets, notably specialty energy and conventional energy, as well as electronics and certain industrial markets.

End-use markets for our products include:

Aerospace & Defense. We are a world leader in the production of specialty materials and components for both commercial and military jet engines and airframes, supporting customer needs for initial build requirements and for spare parts. We believe that through alloy development, internal growth efforts, and long-term supply agreements on current and next-generation jet engines and airframes, we are well-positioned with a fully qualified asset base to meet the expected multi-year demand growth from the commercial aerospace market.

Nickel-based alloys and superalloys remain extremely strong at high temperatures and resist degradation under extreme conditions. Next-generation jet engines use advanced nickel-based superalloys and metallic powder alloys to enable increased fuel efficiency requirements that require hotter-burning engines. Typical aerospace applications for the nickel-based alloys and superalloys and advanced metallic powders we produce include jet engine disks, blades, vanes, rings, casings and shafts. Our specialty materials are also used in the manufacture of aircraft landing gear and structural components.

We are a global industry leader in iso-thermal and hot-die forging technologies for advanced aerospace components. We produce highly sophisticated components that have differing mechanical properties across a single product unit and are highly resistant to fatigue and temperature effects. Our precision forgings are used for jet engine components, structural components

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for aircraft, helicopters, space propulsion, and other demanding applications. ATI provides a full range of post-production inspection and machining with the certified quality needed to meet demanding application requirements.

Additionally, the products and components made from the titanium and titanium-based alloys we produce, such as jet engine components including disks, blades and vanes, and airframe components such as structural members, landing gears, and hydraulic systems, are also critical in aerospace applications. These materials and components possess an extraordinary combination of properties that help to increase jet engine fuel efficiency and product longevity, including superior strength-to-weight ratios, elevated temperature resistance, low coefficient of thermal expansion, and extreme corrosion resistance.

We produce a wide-range of military-grade materials including titanium, nickel-based alloys, zirconium, tungsten, and hafnium, as well as components for our defense customers. Our materials and components are used for many applications, including naval nuclear products, military jet engines, fixed wing and rotorcraft products, armor applications and munitions materials. In fiscal year 2025, sales to our defense end market increased by 14% and we expect continued growth in this important end market in the coming years.

We continuously seek to develop and manufacture innovative new alloys to better serve the needs of the aerospace & defense markets, and several of the alloys we produce have won significant share in current and next-generation jet engines. ATI’s metallic powder technology delivers alloy compositions and refined microstructures that offer increased performance and longer useful lives in high-temperature aerospace environments, as well as improved jet engine efficiency. We continue to increase our production capacity for advanced metallic powders for use in next-generation aerospace products, including additive manufacturing applications. ATI also has a dedicated additive manufacturing and post-processing facility to tap into significant aerospace & defense demand for additively manufactured laser powered bed fusion parts, serving both commercial and defense customers.

Energy. Our products are sold to a variety of end customers in the end-use energy market, with a focus on specialty energy, which includes nuclear power generation and gas turbines. Our high-performance products meet a wide range of needs for protection, conductivity, thermal performance and corrosion resistance. ATI's solutions for the energy industry include specialty materials for solar, geothermal and wind applications, reactor-grade zirconium and hafnium alloys, pioneered by ATI, for nuclear plants; and corrosion-resistant alloys for water systems and scrubbers in coal plants. We believe clean energy needs, the electrification of developing countries, and energy requirements to support data center growth will continue to drive demand for our specialty materials and products for use in these industries over the long term.

Further, we are an industry pioneer in producing nuclear reactor fuel cladding and structural components utilizing zirconium and hafnium alloys for use in nuclear power generation. We also are a technology leader for large diameter components used in natural gas land-based turbines for power generation, and our alloys are used for alternative energy generation, including solar, fuel cell, wind and geothermal applications.

Both of our business segments also produce specialty materials that are critical to the conventional energy market, which includes the oil and gas and chemical and hydrocarbon processing industries. The environments in which oil and gas can be found in commercial quantities have become more challenging, involving deep offshore wells, high pressure and high temperature conditions in sour wells, and other unconventional sources. These challenging offshore environments are located further off the continental shelf, including locations in arctic and tropical waters where drilling is more difficult than previously-sourced locations. Our specialty materials, including nickel-based alloys, duplex alloys and other specialty alloys, have the strength and corrosion-resistant properties necessary to meet these challenging operating conditions. We enable our customers’ success in these applications by developing and producing specialty materials for equipment that can operate for up to 30 years in these harsh environments.

Other Markets. We also serve several other customer end markets, including electronics, medical, and industrial. Customers in the medical end market use ATI’s advanced specialty materials in medical device products that enhance the quality of lives around the world. Manufacturers of magnetic resonance imaging (MRI) devices rely on our niobium superconducting wire to help produce electromagnetic fields that allow physicians to safely scan the body’s soft tissue. Our specialty alloys also are used for replacement knees, hips and other prosthetic devices. The use of our alloys in these replacement devices offers the potential for longer product lifespans versus previous implant generations. Our biocompatible nickel-titanium (nitinol) shape memory alloy is used for stents to support collapsed or clogged blood vessels.

In the electronics market, nickel alloys and Precision Rolled Strip® (PRS) from Specialty Rolled Products (SRP) and our Asian PRS joint venture are used in computers and smart phones. PRS is selected for electronics and communications applications based on corrosion resistance, strength, wear resistance, electrical resistivity or thermal expansion. In addition, metal precursors – which use chemicals produced by ATI, such as hafnium – have a variety of important applications in consumer and industrial electronics.

Finally, ATI's materials and products are used across a wide range of industrial markets, including automotive and construction and mining.

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Business Segments

Our two business segments accounted for the following percentages of total revenues of $4.6 billion, $4.4 billion, and $4.2 billion for the fiscal years ended December 28, 2025, December 29, 2024, and December 31, 2023, respectively.

Information with respect to our business segments is presented below and in Note 18 of the notes to the consolidated financial statements.

High Performance Materials & Components Segment

Our HPMC segment produces a wide range of high performance specialty materials, parts and components for our aerospace & defense, specialty energy, and medical markets, with approximately 92% of fiscal year 2025 revenues derived from the aerospace & defense markets. Most of the products in this segment are sold directly to end-use customers, and a substantial portion of our HPMC segment products are sold under multi-year agreements. Demand for our products is driven primarily by the commercial aerospace cycle. Large aircraft and jet engines are manufactured by a small number of companies, such as The Boeing Company (Boeing), Airbus S.A.S. (an Airbus Group company) including the former operations of Bombardier Aerospace, and Empresa Brasileira de Aeronáutica S.A. (Embraer) for airframes. GE Aerospace, Rolls-Royce plc, Pratt & Whitney (a division of Raytheon Technologies Corporation), and Safran Aircraft Engines. These companies and their suppliers form a substantial part of our customer base in this business segment. We have long-term agreements (LTAs) in place with most major aerospace market original equipment manufacturers (OEMs). The loss of one or more of our customers in the aerospace or defense markets could have a material adverse effect on ATI’s results of operations and financial condition (see Item 1A. Risk Factors).

Within this segment, our products are manufactured from a wide range of advanced materials including metallic powder alloys made from nickel-based alloys and superalloys, titanium and titanium-based alloys, and a variety of other specialty materials. These materials are made into a variety of product forms that include precision forgings, machined parts and others. We are integrated across these alloy systems in melt, forging, finishing, testing and machining processes.

Principal competitors in the HPMC segment include: Berkshire Hathaway Inc., for nickel-based alloys and superalloys and specialty steel alloys, titanium and titanium-based alloys, and precision forgings through its ownership of Precision Castparts Corporation and subsidiaries; Howmet Aerospace Inc., for titanium and titanium-based alloys; Carpenter Technology Corporation for legacy nickel-based alloys and superalloys and specialty steel alloys; and Aubert & Duval for precision forgings.

Advanced Alloys & Solutions Segment

Our AA&S segment produces nickel-based alloys, titanium and titanium-based alloys, and specialty alloys in a variety of forms, including plate and sheet products. The major end markets for our flat rolled products are aerospace & defense, specialty and conventional energy, automotive, medical and electronics markets. The operations in this segment include our Specialty Rolled Products and Specialty Alloys & Components businesses in addition to our Shanghai STAL Precision Stainless Steel Company Limited (STAL) PRS joint venture in China, in which we hold a 60% interest.

Nickel-based alloys, titanium, and stainless sheet products are used in a wide variety of industrial and consumer applications. In fiscal year 2025, approximately 50% of our stainless sheet products by volume were sold to independent service centers, which have slitting, cutting or other processing facilities, with the remainder sold directly to end-use customers.

Nickel-based alloy, titanium, and specialty alloy plate products are primarily used in aerospace & defense, and corrosion and industrial markets. In fiscal year 2025, approximately 40% of our plate products by volume were sold to independent service centers, with the remainder sold directly to end-use customers.

Principal competitors for nickel-based alloys, superalloys, and specialty alloys produced by AA&S include Haynes International and VDM Metals GmbH, a subsidiary of Acerinox S.A.

Raw Materials and Supplies

Substantially all raw materials and supplies required in the manufacture of our products are available from more than one supplier, and the sources and availability of raw materials essential to our businesses are currently adequate. The principal raw materials we use in the production of our specialty materials are scrap (including iron-, nickel-, chromium-, titanium-, and molybdenum-bearing scrap), nickel, titanium sponge, zirconium sand and sponge, ferrochromium, ferrosilicon, molybdenum and molybdenum alloys, manganese and manganese alloys, cobalt, niobium, vanadium, hafnium and other alloying materials. While we enter into raw materials futures contracts from time to time to hedge exposure to price fluctuations, such as for nickel,

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we cannot be certain that our hedge position adequately reduces exposure. We believe that we have adequate controls to monitor these contracts, but we may not be able to accurately assess exposure to price volatility in the markets for critical raw materials.

We source our raw materials through a variety of producers located throughout the world, including the United States (U.S.). The following is a summary of the primary source countries of raw materials that play an important role in our products:

•Nickel: Canada, Norway, Japan, Finland, and South Africa.

•Zirconium: U.S. and China.

•Hafnium: U.S. and China.

•Cobalt: Norway and Japan.

•Chromium: the United Kingdom (U.K.), South Africa, Germany and Turkey.

•Niobium: Brazil.

•Molybdenum: U.S., Brazil, and China.

•Titanium sponge: Japan, Kazakhstan, Saudi Arabia, and China

Some raw materials, such as nickel, titanium sponge, cobalt, and ferrochromium, are mostly available from foreign sources in countries that may be subject to unstable political and economic conditions, which could disrupt supplies or affect the price of these materials. Further, changes in global trade policies could materially impact the total cost of imported materials.

Certain key supplies used in melting and other processing operations, such as graphite electrodes and industrial gases including helium and argon, are from time-to-time limited in availability and may be subject to significant price inflation. We enter into long-term supply contracts where possible to ensure an adequate supply of these products. However, overall industry shortages may impact our operations and scheduling.

Export Sales and Foreign Operations

International sales represent approximately 42% of our total annual sales, with direct export sales by our U.S.-based operations to customers in foreign countries accounting for approximately 34% of our total sales. Our overseas sales, marketing and distribution efforts are aided by our international marketing team or by independent representatives throughout the world. Changes in global trade policies may negatively impact our international sales if export or import tariffs increase the cost of our products.

Our HPMC segment has manufacturing capabilities for precision forging and machining in Poland, primarily serving the aerospace, construction & mining, and transportation markets. Within our AA&S segment, our Asian joint venture makes PRS products, which enables us to offer these products more effectively to markets in China and other Asian countries.

Backlog, Seasonality and Cyclicality

Our backlog of confirmed orders was approximately $3.7 billion at December 28, 2025 and $3.9 billion at December 29, 2024. We expect that approximately 70% of confirmed orders on hand at December 28, 2025 will be filled during fiscal year 2026. Our HPMC segment’s backlog of confirmed orders was approximately $3.1 billion at December 28, 2025 and $3.3 billion at December 29, 2024. We expect that approximately 70% of the confirmed orders on hand at December 28, 2025 for this segment will be filled during fiscal year 2026. Our AA&S segment’s backlog of confirmed orders was approximately $0.6 billion at December 28, 2025 and December 29, 2024. We expect that approximately 90% the confirmed orders on hand at December 28, 2025 for this segment will be filled during fiscal year 2026.

Demand for our products is cyclical over longer periods because specialty materials customers generally operate in cyclical industries and are subject to changes in general economic conditions and other factors both external and internal to those industries. Historically, we have experienced modest seasonal weakness in the third quarter of each fiscal year. This is mostly due to planned outages by certain European customers, particularly those in the aerospace supply chain, that are typically scheduled for the late summer months each year.

Research, Development and Technical Services

We believe that our research and development capabilities give ATI a competitive advantage in developing new products and manufacturing processes that contribute to the long-term profitable growth potential of our businesses. We conduct research and development at our various operating locations both for ourselves and, on a limited basis, for customers on a contract basis. Research and development expenditures for the fiscal years ended December 28, 2025, December 29, 2024, and December 31, 2023 included the following:

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Our research, development and technical service activities are closely interrelated and directed toward development of new products, improvement of existing products, quality assurance, development of new manufacturing methods, improvement of existing manufacturing methods, and reducing our manufacturing costs.

We own hundreds of U.S. patents, many of which are also filed under the patent laws of other nations. Although these patents, as well as our numerous trademarks, technical information, license agreements, and other intellectual property, have been and are expected to be of value, we believe that the loss of any single such item or technically related group of such items would not materially affect the conduct of our business.

Environmental, Health and Safety Matters

We are subject to various domestic and international environmental laws and regulations that govern the discharge of pollutants and disposal of wastes, and which may require that we investigate and remediate the effects of the release or disposal of materials at sites associated with past and present operations. We could incur substantial cleanup costs, fines, civil or criminal sanctions, third party property damage or personal injury claims as a result of violations or liabilities under these laws or non-compliance with environmental permits required at our facilities. We are currently involved in the investigation and remediation of a number of our current and former sites as well as third party sites.

We consider environmental compliance to be an integral part of our operations. We have a comprehensive environmental management and reporting program that focuses on compliance with applicable federal, state, regional and local environmental laws and regulations. Each operating company has an environmental management system that includes mechanisms for regularly evaluating environmental compliance and managing changes in business operations while assessing environmental impact.

Safety is one of our core values. We strive for a zero injury culture committed to the safety of our people, our products, and the communities in which we operate. Nearly all of our domestic employees are working in an ATI facility that has achieved its ISO 45001 certification.

Human Capital Management

We believe that our people and culture are a competitive differentiator. We attract, develop, and retain purpose and performance-driven leaders. Those leaders build teams with diverse, empowered and fulfilled employees who want to stay and grow with the company. As of December 28, 2025, we employed approximately 7,600 active employees, 15% of whom are located outside the U.S. across 15 countries.

Our Culture: At the center of our commitment to excellence are our values, which drive how we succeed: Accountability, Integrity, Innovation, Safety & Sustainability, and Teamwork & Respect.

We continuously strive to cultivate and support a highly engaged and productive workforce. We actively seek opportunities for listening and communication by our CEO and other senior executive leaders with our employees. Periodically, we conduct confidential company-wide engagement surveys that offer our employees the ability to provide feedback, which supports employee engagement and our overall human capital strategy.

Our long tradition of innovation and operational excellence demands the contributions of leaders and team members with a wide array of characteristics, backgrounds, experiences, knowledge, and skills. We believe our business success is intricately tied to cultivating a culture in which all members of our workforce are included and empowered to do their best work.

Governance: The Compensation and Leadership Development Committee of our Board oversees the Company’s human capital management policies and procedures, including its workforce and professional development programs, and is responsible for establishing and administering the policies governing annual compensation and long-term compensation to ensure the policies are designed to align compensation with our overall business strategy and performance to link to the interests of our stockholders.

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Our Code of Conduct establishes the baseline requirements of our integrity and compliance program and promotes an environment where everyone is treated ethically and with respect. It outlines our pledge to recognize the dignity of each individual, respect each employee, provide compensation and benefits that are competitive, promote self-development through training, and value diversity of perspectives and ideas. Employees complete Business Conduct and Ethics training and, where permitted by law, are asked to certify each year that they will comply with the Code.

Talent Acquisition: Our performance and development process is integrated in the ATI business strategy, and is a key component to recruiting, hiring, and developing top-performing talent. We believe in providing an assessment and interviewing process that encourages people from all backgrounds to consider ATI. We partner with top academic institutions that have programs relevant to our business, external professional organizations, trade schools and high schools to identify materials science, STEM and other relevant expertise.

Learning and Development: Developing talent and leaders at all levels of the organization is critical to our long-term success. We have leadership and management development programs as well as broad learning opportunities for our employees to support their career growth and advance their skills. We focus on growing top talent across the enterprise and enhancing Front Line Leader development. Additionally, we maintain a formal talent review process to work in connection with performance management for systematic career development and succession planning at both the individual employee and organizational levels.

Compensation and Benefits: We provide market-based competitive compensation through our salary, annual incentive and long-term incentive programs and robust benefits packages that promote the well-being of our employees across all aspects of their lives. Eligible employees are compensated for their contributions to achievement of our goals with both short-term cash incentives and long-term equity-based incentives. We believe the structure of our compensation packages provides the appropriate incentives to attract, retain, and motivate our employees.

Our well-being focus addresses physical, mental, financial, and individual needs, providing benefits and resources to help employees and their families be their best, both personally and professionally. We have implemented several campaigns to promote well-being and help provide visibility to resources and available benefits. We offer Employee Assistance Programs with therapy sessions to employees and family members, comprehensive mental health benefits to those enrolled in the U.S. medical plan, virtual mental health options and navigation tools to improve access and speed of care, and preventive/mental health resilience programs.

Labor Relations and Collective Bargaining: Approximately 35% of our workforce is covered by various collective bargaining agreements (CBAs), predominantly with the United Steel, Paper and Forestry, Rubber, Manufacturing, Energy, Allied & Industrial Service Workers International Union (USW). On April 22, 2025, we reached agreements with the USW for new CBAs that cover approximately 1,100 USW represented full-time employees within our AA&S operations for a six-year term that extends through February 28, 2031.

Available Information

Our Internet website address is www.atimaterials.com. Our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as well as proxy and information statements and other information that we file, are available free of charge through our Internet website as soon as reasonably practicable after we electronically file such material with, or furnish such material to, the U.S. Securities and Exchange Commission (“SEC”). Our Internet website and the content contained therein or connected thereto are not intended to be incorporated into this Annual Report on Form 10-K. The SEC maintains an Internet website at www.sec.gov, which also contains reports, proxy and information statements and other information that we file electronically with the SEC. We routinely post important information on our website, www.atimaterials.com, in the “Investors” section. We also may use our website as a means of disclosing material, non-public information and for complying with our disclosure obligations under Regulation FD. Accordingly, investors should monitor the Investors section of our website, in addition to following our press releases, SEC filings, public conference calls, presentations and webcasts. The information contained on, or that may be accessed through, our website is not incorporated by reference into, and is not a part of, this document.