Japan Steel Works : Notice Concerning Organizational Change

To whom it may concern

Company name: The Japan Steel Works, Ltd. Name of representative: Toshio Matsuo,

February 9, 2026

Representative Director & President (Code No. 5631 TSE Prime)

Inquiries: Kenji Terada,

General Manager, General Affairs Department (Tel: +81-3-5745-2001)

The Japan Steel Works, Ltd. (the "Company") hereby announces that it has decided to implement organizational changes effective April 1, 2026, as follows.

1. Purpose

   The Company Group has established the medium-term management plan, JGP2028, to simultaneously realize its sustainability target of "Contribute to the realization of a sustainable and prosperous world through development and implementation of industrial machinery and new materials that solve social issues", and its financial target of "net sales of 500 billion yen or more", as its vision for the fiscal year ending March 2034. Under JGP2028, we are working to resolve materiality, enhance corporate value, and develop our management base in order to grow into a corporate group with net sales of 380 billion yen or more by the fiscal year ending March 2029.

   In order to realize a plastic resource recycling society, contribute to a low-carbon society, and contribute to a super-smart society, which are all materiality issues, the Company has decided to implement organizational changes, effective April 1, 2026, which aim to specifically strengthen and accelerate initiatives related to, among the JGP2028 basic policies, "Sustainable improvement of value of existing businesses", and "Creating and nurturing new businesses".

2. Changes in Organization (Effective April 1, 2026)

   1. Establishment of Global Strategy Headquarters

      Aiming for further growth by accelerating global expansion of the Plastics Machinery Business, the Injection Molding Machinery Business, and the Industrial Machinery Business in the Industrial Machinery Segment, the Company will establish a new Global Strategy Headquarters in the Head Office to formulate and promote global strategies in cooperation with business divisions, support and promote strategy formulation tailored to the characteristics of each region and area, strengthen the supervision and governance of overseas subsidiaries, and promote efficiency in administrative operations. The said headquarters will play a central role in global efforts to resolve materiality.

   2. Establishment of Plastics Machinery Solutions Business Division

      To further expand the after-sales service business in the Plastics Machinery Business, we will establish a new Plastics Machinery Solutions Business Division. The Company group, a manufacturer of integrated plastic processing machinery, will as a result build a system to provide services for all plastic machinery products in an integrated manner, and leverage its expertise to further improve customer satisfaction and provide new value, such as stable operation of plastic manufacturing and processing machinery, which is in high demand not only for economic growth, but also for the realization of a low-carbon society, and solving customer issues for the development of new applications.

   3. Establishment of Materials and Engineering Business Division

      As disclosed in the "Notice Concerning Absorption Merger of Consolidated Subsidiaries (Simplified Merger/Short Form Merger)" dated January 19, 2026, the Company will merge with and absorb Japan Steel Works M&E, Inc. (hereinafter referred to as "M&E"), the Company's wholly-owned subsidiary, on April 1, 2026, for the purposes of sustainable growth in the Material and Engineering Business, accelerating the creation of synergies within the Group, and strengthening corporate governance. Along with this, the Company will establish a new Materials and Engineering Business Division as an organization responsible for the Materials and Engineering Business, and will establish Muroran Plant as a manufacturing base for the said business to take over the organization and functions of the M&E Muroran Plant. As a result, we will steadily meet demand for material products for nuclear power generation and high-efficiency thermal power generation, which from the perspective of securing energy security and low-carbon power sources in the long term, and against the backdrop of the rapid spread of artificial intelligence, currently continues its expansion.

   4. Establishment of Photonics Office and Elimination of New Business Promotion Headquarters

With the aim of expanding the photonics business centered on materials for semiconductors and optical devices such as gallium nitride (GaN) and lithium niobate (LN), the organization and functions related to the said business of the New Business Promotion Headquarters will be separated, and a new Photonics Office will be established. As a result, we will strive to significantly expand our business, improve our management capabilities and strengthen governance, with the aim that it will become our core business in the future, while accelerating our efforts to realize a super-smart society.

In addition, the New Business Promotion Headquarters will be eliminated, and the function of commercializing research items will be transferred to the Innovation Management Headquarters, while part of the Composite Material Business will be transferred to the newly-established Materials and Engineering Business Division.

[Medium-Term Management Plan "4 Basic Policies for JGP 2028"]

(Reference) Organizational structure after April 1, 2026

General Meeting of Shareholders

Internal Auditors Office

Board of Directors

Executive Board President

Audit & Supervisory Board

Corporate Planning Office

ESG Promotion Office

Quality Management Office

Office of Information Technology

Office of Digital Transformation Business Development

Office

Innovation Management Headquarters

Personnel Department

General Affairs Department

Finance & Accounting Department Intellectual Property Department

Global Strategy ※

Headquarters

Plastics Machinery Business Division

Plastics Machinery Solutions ※

Business Division

Production Bases

Injection Molding Machinery Business Division

Industrial Machinery Business Division

Ordnance ※

Business Division

Materials and Engineering ※

Business Division

※

Photonics Office

*Indicates new organizations scheduled to be established on April 1, 2026.

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