Amentum Holdings, Inc.

Company to Deliver Digital and Cybersecurity Solutions to Boost Grid Resilience CHANTILLY, Va.--(BUSINESS WIRE)-- Amentum (NYSE: AMTM), a global leader in advanced engineering and technology solutions, has been selected for strategic positions on two significant UK energy frameworks awarded by Scottish and Southern Electricity Networks (SSEN) Transmission.Amentum will deliver cybersecurity services to SSEN Transmission to strengthen UK's energy gridSSEN Transmission is the owner and operator of the high voltage electricity transmission system for the north of Scotland, powering the clean energy transition and delivering a reliable, efficient network that creates lasting benefits for communities, the economy and the environment.“SSEN Transmission is expanding the grid at a pace the UK's energy security depends on, and that growth must be secure by design,” said Matthew Morgan, UK-based group director for Security, Systems and Integration at Amentum. “Our teams will protect critical assets, scale digital capability, and turn operational data into faster, better decisions. We are investing in our team in Scotland to deliver this work, backed by Amentum's deep UK and international experience.”Working from offices in Cardiff, Glasgow, London, and Warrington, Amentum will build upon existing security architecture work the company has performed for SSEN Transmission since 2022.Under three-year agreements, Amentum will leverage its expertise in digital transformation, operational technology (OT), and renewable energy integration to support the UK’s energy transition goals.“The Five Eyes cyber security agencies have recognized the impact of AI in accelerating the speed, scale and sophistication of cyber threats. Leveraging Amentum’s proven expertise in modernizing and securing critical digital infrastructure, we can support SSEN Transmission in addressing one of the most serious challenges of our time,” said Jennifer Walsmith, president of Intelligence & Cyber at Amentum. “We look forward to delivering the innovation and security needed to strengthen the UK’s energy future.”About Amentum Amentum is a global leader in advanced engineering and innovative technology solutions, trusted by the United States and its allies to address their most significant and complex challenges in science, security and sustainability. Our people apply undaunted curiosity, relentless ambition and boundless imagination to challenge convention and drive progress. Our commitments are underpinned by the belief that safety, collaboration and well-being are integral to success. Headquartered in Chantilly, Virginia, we have approximately 50,000 employees in more than 70 countries across all 7 continents.About Amentum in the United Kingdom With more than 6,000 people in the UK, Amentum is the delivery partner for project and construction management services at Hinkley Point C; sole program and project management delivery partner at Sizewell C; and also supports the UK’s existing nuclear power stations under a

CHANTILLY, Va.--(BUSINESS WIRE)-- Amentum (NYSE: AMTM) has been awarded the Center Maintenance, Operations, and Engineering II (CMOE II) contract at NASA Langley Research Center in Hampton, Virginia, a renowned hub for scientific discovery and innovation. The award reaffirms Amentum’s role as a trusted partner in advancing NASA’s groundbreaking research, technology development, and exploration goals. Image credit: NASA Langley / David C. Bowman “The scope of solutions and capabilities we deliver will ensure NASA Langley sustains its critical role in advancing space science and deep space exploration. Amentum’s technical expertise and agile management strategies have been instrumental in supporting NASA’s vision for solving critical challenges and driving future innovation,” said Mark Walter, president of Amentum’s Engineering and Technology business. Under the CMOE II contract, Amentum will deliver cutting-edge support for advanced research systems such as wind tunnels, laboratories, and research utilities. Amentum will also provide advanced engineering expertise including design, project, construction, and configuration management, and pressure system recertification. Finally, Amentum will deliver vital mission capabilities, including preventive maintenance, repairs, and central utilities operations across NASA Langley’s institutional and research facilities. Amentum has been a dedicated partner to NASA for over six decades, consistently delivering innovative, safe, and sustainable solutions to meet the agency’s evolving needs. Through this new contract, the company will continue to play a key role in advancing Langley’s success by managing complex systems, optimizing operational processes, and spearheading critical capital improvements. These efforts include modernizing NASA Langley’s infrastructure, including automating laboratory systems and wind tunnel testing facilities. The CMOE II award reinforces Amentum’s commitment to maintaining the reliability and excellence of NASA Langley’s world-class facilities. About Amentum Amentum is a global leader in advanced engineering and innovative technology solutions, trusted by the United States and its allies to address their most significant and complex challenges in science, security and sustainability. Our people apply undaunted curiosity, relentless ambition and boundless imagination to challenge convention and drive progress. Our commitments are underpinned by the belief that safety, collaboration and well-being are integral to success. Headquartered in Chantilly, Virginia, we have approximately 50,000 employees in more than 70 countries across all 7 continents. Visit us at amentum.com to learn how we advance the future together. Follow <a href="https://cts.businesswire.com/ct/CT?id=smartlink&amp;url=https%3A%2F%2Ftwitter.com%2Famentum_corp&amp;esheet=54592157&amp;newsitemid=20260820114703&am

Award from Babcock enables support across nuclear, marine, land and aviation domains CHANTILLY, Va.--(BUSINESS WIRE)-- Amentum (NYSE: AMTM) has joined a five-year Babcock International Group Engineering Services Framework to support nuclear, marine, land, aviation and mission systems for the UK Armed Forces at home and abroad.Image courtesy of Babcock International GroupThe agreement forms part of a wider strategy to build closer, long-term partnerships with key suppliers, creating a simpler and more consistent way to bring specialist engineering expertise into critical defence programmes. The framework enables suppliers to support multiple projects more quickly, helping streamline procurement and strengthen collaboration.The award of the framework builds on decades of infrastructure support to Babcock’s Devonport Royal Dockyard, His Majesty’s Naval Base Clyde, and the Rosyth Royal dockyard, and enables on-going and future support to critical UK defence and submarine programmes, as well as broader support for platforms and infrastructure across the nuclear, marine, land, and air domains.“Our decades of naval nuclear infrastructure experience, the breadth and depth of our engineering and architectural skills, together with our unrivalled scientific reach back, makes Amentum a one-stop shop for Babcock’s engineering, nuclear and technical requirements,” said Loren Jones, senior vice president and head of Amentum’s Energy & Environment-International business. “We are looking forward to supporting the delivery of programmes vital to the UK’s safety and security in the years ahead, deploying our proven experience of modernizing the UK’s naval bases, dockyards and defence systems, including specialized technical validation for critical infrastructure such as docks, berths and shiplifts for the maintenance of Astute and Dreadnought-class submarines, and for the wider Royal Navy fleet.”Amentum provides complex programme, project and engineering solutions, including: requirements management; architectural design and building services; multi-disciplinary design engineering (marine, civil / structural, electrical, control and instrumentation and mechanical); and specialist technical support, such as safety case authoring, Human Factors, 3D Building Information Modelling, geotechnical studies, seismic / blast assessment and Independent Technical Assessment. Amentum also supports critical defence programmes more widely, providing research and technology services, safety case, and security services for the Royal Navy’s nuclear propulsion systems.About Amentum Amentum is a global leader in advanced engineering and innovative technology solutions, trusted by the United States and its allies to address their most significant and complex challenges in science, security and sustainability. Our people apply undaunted curiosity, relentless ambition and boundless imagination to challenge convention and drive progress. Our commitments are underpinned by the belief that safety, collaboration and well-being are integral to success. Headquartered in Chantilly, Virginia, we have approximate

CHANTILLY, Va.--(BUSINESS WIRE)-- Australian Naval Infrastructure (ANI) selected a joint venture between Amentum (NYSE: AMTM) and Laing O’Rourke as its Capability Partner to support the delivery of a nuclear-powered submarine construction yard in South Australia. Osborne Naval Shipyard, South Australia Under a long-term contract, Amentum and Laing O’Rourke will play a central role in developing the new shipyard at Osborne, north of Adelaide, where Australia’s nuclear-powered submarines will be built as part of the AUKUS trilateral agreement. “Amentum has the opportunity to be part of a once-in-a-generation national endeavor that will shape Australia’s sovereign nuclear capability for decades,” said Mark Whitney, president of Amentum Energy & Environment. “We bring more than 60 years of global expertise in nuclear submarine programs, significant nuclear licensee experience, independent regulator exposure and a clear pathway for growing enduring Australian nuclear capability.” “Our team will provide hands-on leadership across key areas of delivery, including governance, assurance, logistics, commissioning, digital engineering, supply chain quality, and integrating construction expertise into the design phase,” said Kim Katheklakis, Amentum Australia managing director. The Capability Partner will provide nuclear-related program management, construction management and safety leadership within ANI’s Integrated Delivery Office. The partnership will collaborate closely with ANI to coordinate work packages, support contractor engagement and ensure seamless interface management across the nuclear and non-nuclear areas of the submarine construction yard. The new construction yard will enable Australia to build and sustain conventionally armed, nuclear‑powered submarines for the first time. It will house the advanced facilities required for assembly, outfitting, testing and commissioning of the future SSN‑AUKUS fleet. This project is critical to strengthening Australia’s long‑term national security, deepening defense industrial capability, and creating thousands of highly skilled jobs in South Australia. As part of the AUKUS partnership with the United States and United Kingdom, the program will position Australia as a key contributor to stability in the Indo‑Pacific region. About Amentum Amentum is a global leader in advanced engineering and innovative technology solutions, trusted by the United States and its allies to address their most significant and complex challenges in science, security and sustainability. Our people apply undaunted curiosity, relentless ambition and boundless imagination to challenge convention and drive progress. In Australia, Amentum has more than 1,000 team members delivering engineering, program and project management services to government and commercial clients in a range of sectors including defense and national security, cyber and digital, energy and environment, and critical infrastructure. With the AUKUS program accelerating, we are growing our team and capabilities to support the establishment of sovereign nuclear capability in Australia – from the construction of nuclear-licensed facilities and nuclear-powered submarines to through-life operations, decommissioning, disposal, cleanup, and radioactive waste management. Visit us at <a href="https://cts.businesswire.com/ct/CT?id=smartlink&amp;url=http%3A%2F%

CHANTILLY, Va.--(BUSINESS WIRE)-- Amentum (NYSE: AMTM) has been selected by the U.S. Department of Energy’s National Nuclear Security Administration (NNSA) to enter negotiations for a phased lease to develop one of the nation’s largest integrated artificial intelligence and energy infrastructure projects at the Savannah River Site (SRS) in South Carolina. Once finalized, the public-private project would establish a 1-gigawatt artificial intelligence data center supported by approximately 2 gigawatts of on-site energy generation, initially powered by natural gas bridging to advanced nuclear energy. data center stock footage “Artificial intelligence, energy resilience, and national security are becoming increasingly interconnected, creating new opportunities to strengthen America’s strategic advantage,” said John Heller, Chief Executive Officer of Amentum. “Amentum is uniquely positioned at that intersection, combining deep engineering expertise, trusted mission execution, and decades of partnership with the U.S. government. This agreement gives us the opportunity to partner with the NNSA to deliver infrastructure that will help power the technologies shaping our nation’s future.” Artificial intelligence is transforming the way governments, industries and societies operate – and its continued advancement depends on resilient, secure energy infrastructure capable of powering the next generation of computing. “For generations, Amentum has helped solve some of the nation’s most complex engineering and nuclear challenges, including at the Savannah River Site,” said Mark Whitney, president of Amentum’s Energy & Environment business. “This opportunity builds on that legacy by bringing together our expertise in nuclear operations, infrastructure development, and program delivery to help our customer safely and securely accelerate the next generation of AI and energy infrastructure.” The SRS data center project is designed to accelerate domestic AI computing capacity, expand reliable power generation, and demonstrate how public-private partnerships can advance innovative technologies while strengthening America’s critical infrastructure. As demand for advanced technologies continues to grow, Amentum remains committed to delivering the engineering excellence, trusted partnerships, and mission-focused innovation that help customers strengthen national security, enhance energy resilience, and build the critical infrastructure that will define the future. About Amentum Amentum is a global leader in advanced engineering and innovative technology solutions, trusted by the United States and its allies to address their most significant and complex challenges in science, security and sustainability. Our people apply undaunted curiosity, relentless ambition and boundless imagination to challenge convention and drive progress. Our commitments are underpinned by the belief that safety, collaboration and well-being are integral to success. Headquartered in Chantilly, Virginia, we have approximately 50,000 employees in more than 70 countries across all seven continents. Visit us at amentum.com to learn how we advance the future together.Follow <a href="https://cts.businesswire

CHANTILLY, Va.--(BUSINESS WIRE)-- Amentum (NYSE: AMTM), a global leader in advanced engineering and innovative technology solutions, will host a conference call on August 11, 2026, at 8:30 AM EDT to discuss financial results for the third quarter fiscal year 2026 ending July 3, 2026. A news release containing the results will be issued prior to the call. Amentum Q3 FY26 Earnings Call 8:30am August 11 The conference call will be webcast to the public through a link on Amentum’s Investor Relations Website. A replay of the conference call, along with the earnings press release, presentation slides and supplemental financial disclosures, will be available via the same link. About Amentum Amentum is a global leader in advanced engineering and innovative technology solutions, trusted by the United States and its allies to address their most significant and complex challenges in science, security and sustainability. Our people apply undaunted curiosity, relentless ambition and boundless imagination to challenge convention and drive progress. Our commitments are underpinned by the belief that safety, collaboration and well-being are integral to success. Headquartered in Chantilly, Virginia, we have approximately 50,000 employees in more than 70 countries across all 7 continents. Visit us at amentum.com to learn how we advance the future together. Follow @Amentum_corp on X Follow Amentum on LinkedIn Media Contact: Chanel Mann chanel.mann@amentum.com Investor Contact: Joseph DeNardi IR@amentum.com <span class="

CHANTILLY, Va.--(BUSINESS WIRE)-- Amentum (NYSE: AMTM), a global advanced engineering and technology company, has been named to the list of America’s Best Companies 2026 by TIME Magazine. America’s Best Companies, an annual ranking by TIME magazine in partnership with Statista, identifies top-performing U.S. companies using a data-driven evaluation across employee satisfaction, financial strength, and sustainability transparency. TIME America's Best Companies 2026 in partnership with Statista “Recognition in TIME Magazine’s America’s Best Companies 2026 is an accolade reflecting the tremendous efforts and commitment of our employees, whose talent and dedication make Amentum a leader in solving the world’s science, security and sustainability challenges,” said John Heller, Amentum chief executive officer. "We strive for excellence not just in what we achieve, but also in how we operate—with integrity, purpose, and a focus on impact for our clients and stakeholders.” “This recognition is a direct reflection of our people-first culture and the incredible community we have built at Amentum. We prioritize the needs of our team members because we know they are the foundation of our success,” said Darren Burton, Amentum chief people officer. “This award also highlights our ongoing efforts to create a sustainable future through responsible business practices and thoughtful governance. I want to thank every employee who helped make this award possible – your voice, dedication, and contributions are what truly place Amentum among the best." About Amentum Amentum is a global leader in advanced engineering and innovative technology solutions, trusted by the United States and its allies to address their most significant and complex challenges in science, security and sustainability. Our people apply undaunted curiosity, relentless ambition and boundless imagination to challenge convention and drive progress. Our commitments are underpinned by the belief that safety, collaboration and well-being are integral to success. Headquartered in Chantilly, Virginia, we have approximately 50,000 employees in more than 70 countries across all 7 continents. Visit us at amentum.com to learn how we advance the future together.Follow @Amentum_corp</a

CHANTILLY, Va.--(BUSINESS WIRE)-- Amentum (NYSE: AMTM), a global leader in advanced engineering and technology solutions, has been awarded NASA’s Consolidated Spaceflight Mission Operations and Systems (COSMOS) contract. The award comes through the ASCEND Aerospace & Technology, LLC, a joint venture between Amentum and Aerodyne Industries, LLC, formed under the Small Business Administration’s Mentor-Protégé Program. Mission Control Center at NASA’s Johnson Space Center; image courtesy of NASA The COSMOS work reinforces Amentum's vital role in the U.S. space program in support of the NASA mission to explore new frontiers and advance human understanding. “Amentum’s proven track record in enabling complex spaceflight missions makes us an ideal partner to advance U.S. leadership in space,” said Mark Walter, president for the Engineering and Technology business at Amentum. “Through the ASCEND partnership, we’re delivering the space systems and training solutions to facilitate NASA’s ambitious goals for deep-space exploration and scientific discovery.” Under the COSMOS contract, ASCEND will deliver critical mission operations, systems, and training solutions to support NASA’s Flight Operations Directorate at the Johnson Space Center in Houston, Texas. This work will play a vital role in advancing some of NASA’s most complex and high-profile programs, including the Orion and Space Launch System (SLS) programs which enable future deep-space exploration as well as International Space Station (ISS) operations and astronaut training programs. Additional programs include the Commercial Crew Program, which expands access to low-Earth orbit and the Artemis program, aimed ultimately at developing a sustained human presence on the lunar surface. Amentum will provide expertise in Mission Control Center systems, training for both astronauts and instructors, flight controller readiness, training systems development, and mockup environments that replicate real-world conditions, delivering mission-ready solutions as a trusted partner to NASA and the U.S. space enterprise. About Amentum Amentum is a global leader in advanced engineering and innovative technology solutions, trusted by the United States and its allies to address their most significant and complex challenges in science, security and sustainability. Our people apply undaunted curiosity, relentless ambition and boundless imagination to challenge convention and drive progress. Our commitments are underpinned by the belief that safety, collaboration and well-being are integral to success. Headquartered in Chantilly, Virginia, we have approximately 50,000 employees in more than 70 countries across all 7 continents. Visit us at amentum.com to learn how we advance the future together. Follow <a href="https://cts.businesswire.com/ct/CT?id=smartlink&amp;url=https%3A%2F%2Ftwitter.com%2Famentum_corp&amp;esheet=54562318&amp;newsitemid=20260630

CHANTILLY, Va.--(BUSINESS WIRE)-- Amentum (NYSE: AMTM) will deliver logistics operations support under a new 60-month firm-fixed price contract awarded by the General Services Administration (GSA) to provide modernized, end-to-end, AI-powered supply chain solutions for the Pentagon and other federal customers operating across Japan as part of the U.S. Indo-Pacific Command (INDOPACOM) area of responsibility. Amentum will enhance operational readiness in a strategic region by ensuring seamless supply chain management for U.S. military installations. Kadena Air Base, Okinawa Japan “Amentum’s new relationship with the GSA is a natural fit given our unique global supply chain reach, forward-positioned operational capability and expeditionary sustainment,” said Dr. Karl Spinnenweber, president of Amentum’s Mission Solutions business. "Our extensive experience in delivering turnkey supply chain solutions worldwide ensures we can support the GSA and INDOPACOM with predictability, reliability, and efficiency.” Amentum has integrated these capabilities into a single, agile framework to ensure seamless operations in contested, austere and politically sensitive environments. AI tools will be incorporated into the program to enhance demand planning, forecasting and catalog management to improve customer order fulfillment and delivery. Amentum will implement a comprehensive approach to supply chain management, delivering tailored solutions to ensure uninterrupted operational sustainment. The company is leveraging technology solutions to monitor, analyze, and optimize supply chain activities, including demand forecasting, procurement, transportation, inventory management, and on-time delivery. About Amentum Amentum is a global leader in advanced engineering and innovative technology solutions, trusted by the United States and its allies to address their most significant and complex challenges in science, security and sustainability. Our people apply undaunted curiosity, relentless ambition and boundless imagination to challenge convention and drive progress. Our commitments are underpinned by the belief that safety, collaboration and well-being are integral to success. Headquartered in Chantilly, Virginia, we have approximately 50,000 employees in more than 70 countries across all 7 continents. Visit us at amentum.com to learn how we advance the future together. Follow @Amentum_corp on X Follow <a href="https://cts.businesswire.com/ct/CT?id=smartlink&amp;url=https%3A%2F%2Fwww.linkedin.com%2Fcompany%2Famentumcorp%2F&amp;esheet=54555527&amp;newsitemid=20260617598302&amp;lan=en-US&amp;anchor=Amentum&amp;index=4&amp;md5=c07