Business Description

Constellium SE, a Societas Europaea (“SE”) incorporated under the law of France with its head office located at Washington Plaza 40-44 rue Washington, Paris, France, is the parent company of the Group. Unless the context indicates otherwise, when we refer to “we,” “our,” “us,” “Constellium,” the “Group” and the “Company” in this document, we are referring to Constellium SE and its subsidiaries. On June 30, 2025, the Company determined it no longer qualified as a “foreign private issuer”. As from January 1, 2026, when its earlier submission to the US securities law requirements applicable to a domestic issuer ceased to be voluntary, the Company will continue to file annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and comply with all other obligations applicable to companies not qualifying as “foreign private issuers” as set forth by the New York Stock Exchange (“NYSE”) and the Securities and Exchange Commission (“SEC”). The Group’s U.S. assets are held by Constellium US Holdings I, LLC, a wholly owned subsidiary of Constellium SE. The I.R.S. Employer Identification Number of Constellium US Holdings I, LLC is: 27-4126819. Overview We are a global leader in the development, manufacture and sale of a broad range of high value-added specialty rolled and extruded aluminum products to the aerospace, space, defense, packaging, automotive, commercial transportation and general industrial end-markets. Our business model is to add value by converting aluminum into semi-fabricated and in some instances fully-fabricated alloyed aluminum products which meet stringent and performance-critical requirements from our customers. Our product portfolio generally commands higher margins as compared to less differentiated, more commoditized aluminum products. Our business model aims to pass through aluminum price exposure by pricing our products to include the cost of the metal purchased and hedging any remaining exposure to achieve aluminum price neutrality. At December 31, 2025 , we have 24 manufacturing facilities, 3 Research and Development ( “R&D” ) centers, and 3 administrative centers. Our portfolio of flexible, integrated and strategically located facilities is well invested, technologically advanced and competitively positioned. We believe that we are a critical supplier to many of our customers given our world- class technological and R&D capabilities, our intellectual property and more than 50 years of manufacturing experience. Many of our products are technically advanced, requiring long and complex qualification processes as well as the need for close customer collaborations including joint product development. We believe that our strategic footprint, differentiated capabilities, technically advanced product portfolio, integrated approach and long-standing customer relationships are difficult to replicate and support our competitive position. Our Strategy Our mission is to meet customers’ and society’s need for lightweight, strong and sustainable aluminum products while generating attractive returns for our shareholders. We aim to achieve our mission by expanding our leading position as an innovative, go-to-supplier of technologically advanced fabricated aluminum solutions. We are committed to building a safe and sustainable company and becoming the most exciting company in our industry. To achieve these objectives, we have built a business strategy centered around six core principles: 2 (i) Focus on High Value-added and Responsible Products We are primarily focused on our strategic end-markets including aerospace, packaging and automotive, in which we have leading positions and long-standing relationships with many of the key manufacturers. These are also markets where we believe we can differentiate ourselves through our high value-added and specialty products which make up the majority of our product portfolio. Because aluminum is lightweight, strong, durable, and infinitely recyclable, we have invested heavily in advancing our manufacturing and recycling capabilities. These improvements deliver products that reduce weight, increase strength, and improve formability, helping customers meet their carbon‑reduction objectives. (ii) Increase Customer Connectivity We regard our relationships with our customers as partnerships in which we work closely together to develop technically advanced and customized solutions.…