Here are a few analogies to describe Amentum (AMTM):

• Booz Allen Hamilton for advanced engineering and global government challenges.
• Leidos for global, complex engineering and national security solutions.

• Science Solutions: Providing advanced engineering and innovative technology solutions to address complex challenges in scientific research, development, and operational support.
• Security Solutions: Delivering advanced engineering and innovative technology solutions for national security, defense, and intelligence challenges for governmental clients.
• Sustainability Solutions: Offering advanced engineering and innovative technology solutions to tackle environmental issues, energy management, and infrastructure resilience.

Amentum (AMTM) primarily serves governmental entities rather than other public companies or individuals. Its major customers include:

• United States Department of Defense (DoD): This encompasses various branches and agencies, including the Army, Navy, Air Force, Marine Corps, and other defense-related organizations.
• United States Department of Energy (DoE): Amentum holds significant contracts for managing national laboratories and nuclear facilities under the DoE.
• United States National Aeronautics and Space Administration (NASA): Providing support for space exploration and related programs.
• United States Department of State: Offering support for diplomatic and foreign policy initiatives.
• United States Department of Homeland Security (DHS): Contributing to national security and emergency preparedness efforts.
• Allied Governments: Amentum also provides its services and solutions to various international governments that are allies of the United States.

These customers are governmental agencies and do not have public company symbols.

John Heller, Chief Executive Officer

John Heller was appointed CEO of Amentum in March 2022, having previously served as CEO of the legacy Amentum company since 2022 where he led the integration of two multi-billion-dollar acquisitions. Prior to Amentum, he was the Chief Executive Officer and President of PAE, which he guided to become a publicly traded company. He also served as Chief Executive Officer of Netco, Inc., a Cerberus Capital Management (private equity) portfolio company, overseeing its sale to Harris Corp. His first CEO position was at Rentport, Inc., a company backed by Catterton Partners (now L Catterton), a private equity firm. Heller's career also includes roles as Senior Vice President and Chief Operating Officer of Engility Corporation and leadership positions at Harris Corporation.

Travis Johnson, Chief Financial Officer

Travis Johnson was appointed Chief Financial Officer of Amentum in July 2023. In this role, he is responsible for all financial activities, including accounting, finance strategy, business operations, planning and analysis, treasury, and investor relations. Before joining Amentum, Johnson served as Senior Vice President, Corporate Controller, and Chief Accounting Officer at CACI. He also held the Chief Accounting Officer position at FLIR Systems and KeyW Corporation, where he led transformation efforts that resulted in the sale of both companies. His experience also includes various finance leadership roles at Leidos and a start to his career in public accounting at RSM.

Dr. Stephen (Steve) Arnette, Chief Operating Officer

Dr. Stephen Arnette serves as the Chief Operating Officer for Amentum, a role he assumed effective September 27, 2024. He is responsible for leading business operations and supporting strategic growth initiatives for the company. Prior to the Amentum-Jacobs Critical Mission Solutions business merger in 2024, Arnette was Jacobs' Executive Vice President and President of the Critical Mission Solutions (CMS) line of business. He has over 29 years of experience at Jacobs, holding various senior leadership positions across multiple sectors and operations, including leading the AERO business unit and serving as General Manager of Jacobs' Technology Group.

Sean Mullen, Chief Growth Officer

Sean Mullen serves as the Chief Growth Officer at Amentum, responsible for leading the company's business development and growth strategy. He joined Amentum in 2022 as Executive Vice President of Business Development and was appointed to his current role following the September 27, 2024 transaction. With a career spanning over 30 years, Mullen has held growth leadership roles at companies such as Perspecta, HP Enterprise Services, and Northrop Grumman, and began his career as a civilian employee with the U.S. Air Force.

Michele St. Mary, Chief Legal Officer and General Counsel

Michele St. Mary was appointed Chief Legal Officer and General Counsel for Amentum, effective February 17, 2025. In this role, she oversees Amentum's legal, ethics, compliance, contracts, and security functions globally. St. Mary brings over 25 years of experience in the government contracting industry. Before joining Amentum, she spent 19 years at L3Harris Technologies, most recently as Vice President, Deputy General Counsel, and Assistant Secretary, where she provided legal oversight for mergers and acquisitions and strategic integrations. Her prior experience also includes roles as Senior Counsel for Sun Microsystems, Inc. and an associate at Crowell & Moring LLP.

1. Reliance on U.S. Government Contracts and Spending Volatility: Amentum is highly dependent on contracts with the U.S. government and its allies. This reliance exposes the company to risks associated with shifts in governmental budgetary priorities, potential funding delays, administrative hurdles, and government shutdowns, all of which can negatively impact revenue generation and growth.
2. Contract Execution and Performance: The company faces risks related to its ability to effectively manage project costs, adhere to performance requirements, and meet contractual schedules. Additionally, the timing of significant project ramp-ups and the ability to secure new contracts are crucial. Amentum has also experienced the loss of legacy contracts, which can create near-term revenue challenges.
3. Execution of Deleveraging Plan and Financial Flexibility: Amentum's strategy to reduce its debt is contingent upon consistent EBITDA growth and prudent capital allocation. The company also faces potential near-term cash flow pressures, which could affect its financial flexibility and deleveraging efforts.

Amentum (AMTM) operates within several significant addressable markets, primarily focused on government and commercial services in advanced engineering, technology solutions, nuclear and environmental remediation, and defense.

Here are the addressable market sizes for Amentum's main products and services:

• Engineering Services (Advanced Engineering and Innovative Technology Solutions):
  • The global engineering services market was valued at approximately USD 2.34 trillion in 2025 and is projected to grow to USD 5.37 trillion by 2034, with a compound annual growth rate (CAGR) of 10.60% from 2026 to 2034. Other estimates place the global market size at USD 3.66 trillion in 2025, expected to reach around USD 5.74 trillion by 2035.
  • For North America, the engineering services market is expected to reach approximately USD 1.36 trillion by 2035, growing from USD 0.86 trillion in 2025. The U.S. market specifically is estimated at USD 0.45 trillion in 2026.
• Nuclear Services and Solutions:
  • The global nuclear plant services market was over USD 74.38 billion in 2025 and is poised to exceed USD 122.32 billion by 2035.
  • The global nuclear engineering service market is valued at USD 33.208 billion in 2025 and is projected to reach USD 64.115 billion by 2035, growing at a CAGR of 6.8%.
• Environmental Remediation and Solutions:
  • The global environmental remediation market is projected to reach USD 210.56 billion in 2030 from USD 141.87 billion in 2025, growing at a CAGR of 8.2% during the forecast period.
  • The U.S. environmental remediation market is expected to grow from USD 23.37 billion in 2025 to an estimated USD 38.53 billion by 2033, with a CAGR of 6.45%.
  • The global environmental technology market is estimated to be valued at USD 714.74 billion in 2025 and is expected to reach USD 1,054.29 billion by 2032.
• Defense and Government Services:
  • The global defense market reached approximately USD 473.47 billion in 2024 and is expected to grow to USD 682.10 billion in 2029. Another report estimates the global defense market at USD 566.137 billion in 2025, increasing to USD 874.003 billion by 2032.
  • Global defense spending is expected to grow from USD 2.7 trillion in 2024 to USD 6.38 trillion by 2035.
  • North America is estimated to hold a substantial share of the defense spending market, with the U.S. alone spending USD 997 billion in 2024.
  • The mission systems segment, which includes areas like C5ISR systems engineering where Amentum operates, accounted for 37.71% or USD 178.55 billion of the total global defense market in 2024.

Amentum (AMTM) is strategically positioned to capitalize on several key drivers for future revenue growth over the next two to three years:

• Expansion in the Global Nuclear Energy Market: Amentum anticipates increased revenue contributions from recently secured nuclear contracts, particularly in Europe and emerging U.S. projects. The company highlights strong secular demand drivers in the global nuclear market, including growing energy requirements for AI data centers, industrial applications, and national security priorities, projecting an 8% compound annual growth rate (CAGR) for this market between fiscal year 2026 and 2030. Amentum has secured significant nuclear energy contracts, such as a 10-year contract with EDF Nuclear Power and a partnership with Rolls-Royce on small modular reactors.
• Growth in Space Systems and Technologies: Amentum is actively expanding its portfolio in space systems, which is identified as an "accelerating growth market." This includes winning contracts for satellite integration, missile defense, and providing support for U.S. and allied national security programs. Notable wins include a $4 billion United States Space Force single-award IDIQ contract over ten years.
• Development of Critical Digital Infrastructure and AI-Driven Opportunities: The company views critical digital infrastructure as another "accelerating growth market." Its Digital Solutions segment has shown strong growth, driven by new contract awards in this area, including the commercial digital infrastructure market. Amentum expects to benefit from substantial investments in AI data centers, which are accelerating opportunities within this sector.
• Conversion of Robust Backlog into Revenue: Amentum maintains a substantial backlog, reported at over $47 billion, which provides significant visibility for future revenue. The company has consistently achieved a book-to-bill ratio at or above 1x for multiple consecutive quarters, indicating a healthy pipeline of new business awards. The conversion of these large contract wins, particularly in nuclear and space-related areas, into recognized revenue is a critical driver for top-line growth.

Share Issuance

• Amentum Holdings, Inc. had 243,302,173 shares issued and outstanding as of September 27, 2024.
• As of November 14, 2025, there were 243,597,992 shares of Amentum Holdings, Inc. common stock outstanding.
• A secondary public offering of 19,464,174 shares was priced on March 12, 2025; Amentum itself did not sell any shares or receive proceeds from this offering.

Outbound Investments

• During Q3 FY25, Amentum utilized $360 million in gross proceeds from the divestiture of its Rapid Solutions business to pay down debt.
• Net contributions to equity method investments totaled $27 million in Q1 FY2026.

Capital Expenditures

• Capital expenditures were $11 million in 2023, $12 million in 2024, and $18 million in 2025.
• For Q1 FY2026 (ended January 2, 2026), capital expenditures amounted to $6 million.