TSUNEISHI IRON WORKS Co., Ltd. (Head Office: Fukuyama, Hiroshima, Japan; hereinafter ‘TSUNEISHI IRON WORKS’) has acquired all shares of KOTOBUKI IRON WORKS Co., Ltd. (Head Office: Aioi, Hyogo, Japan; hereinafter ‘KOTOBUKI IRON WORKS’) , which was previously a consolidated subsidiary of IHI Corporation, from IHI Corporation (Head Office: Koto-ku, Tokyo, Japan; hereinafter ‘IHI’), effective 1st February 2026. As a result, KOTOBUKI IRON WORKS has become a wholly owned subsidiary of TSUNEISHI IRON WORKS,

Through this acquisition, TSUNEISHI IRON WORKS aims to create synergies by leveraging the advanced technologies cultivated by KOTOBUKI IRON WORKS and to further expand its overall production capacity.

Established in 1947, KOTOBUKI IRON WORKS has built a strong track record in steel structure manufacturing, machining, steel processing, pressure vessel manufacturing and maintenance services. The company has developed extensive expertise in ironworking technologies, particularly for the shipbuilding industry, and is widely recognised for its strengths in manufacture of marine engine frames and large-scale structures such as equipment for thermal power plants. These advanced capabilities are expected to play an important role in TSUNEISHI IRON WORKS’ expansion into new business domains.

With the acquisition, TSUNEISHI IRON WORKS will extend its business footprint into Kansai region, complementing its existing sites in the Chugoku and Kyushu regions. This expanded network is expected to enhance competitiveness by strengthening overall production capacity across western Japan and optimising logistics efficiency.

Going forward, TSUNEISHI IRON WORKS will continue to further develop the technologies fostered by KOTOBUKI IRON WORKS, reinforce its core businesses and actively pursue new fields, with the aim of enhancing long-term corporate value.

Message from the President
Mr SHIMOMURA Naoya, President of TSUNEISHI IRON WORKS Co., Ltd. commented:
“We would like to express our sincere gratitude to all stakeholders for their continued support in completing the acquisition of KOTOBUKI IRON WORKS, which has now become a wholly owned subsidiary of TSUNEISHI IRON WORKS. The proven technologies and extensive experience that KOTOBUKI IRON WORKS has built up over many years will be a significant asset to our company.

Through the acquisition, we will establish a production network covering the whole of western Japan and build an organisation capable of exceeding our customers’ expectations in both speed and quality. By combining the strengths of both companies, we aim to create new value within the ironworks industry and achieve sustainable growth.”

TSUNEISHI IRON WORKS will continue to take on further challenges without being afraid of change, bringing together the strength of the entire group to carve out a new future.

■Company Overview: IHI Corporation
Corporate Name: IHI Corporation
Representative: IDE Hiroshi, CEO
Head Office: TOYOSU IHI BUILDING., 1-1, Toyosu 3-chome, Koto-ku, Tokyo 135-8710, Japan
Founded: December 5, 1853
Capital: JPY 107.1 billion
Business Activities: Resources & Energy & Environment Business Area, Social Infrastructure Business Area, Industrial Systems & General-Purpose Machinery Business Area, Aero Engine & Space & Defense Business Area
Website: https://www.ihi.co.jp/en/

■Company Overview: KOTOBUKI IRON WORKS Co., Ltd.
Corporate Name: KOTOBUKI IRON WORKS Co., Ltd.
Representative: ISHINO Toshifumi, President
Head Office: 19-47, Asahi 1-chome, Aioi, Hyogo 678-0031, Japan
Founded: December 4, 1947
Capital: JPY 76.8 million
Business Activities: Manufacturing of Power & Chemical Plant Components, Turbine Casings, and Diesel Engine Parts
Website: https://www.tsuneishi.co.jp/kotobuki/

■TSUNEISHI IRON WORKS Co., Ltd.
TSUNEISHI IRON WORKS produces various outfitting products, including hull blocks and stern frames, and is responsible for supplying them to TSUNEISHI SHIPBUILDING and its overseas subsidiaries in the shipbuilding business, as well as for outfitting work. In addition to the shipbuilding business, we also produce onshore structures such as floating piers and bridges. The Wakamatsu Steel Plant (Wakamatsu-ku, Kitakyushu, Fukuoka, Japan), which started operations in April 2014, utilises large facilities such as electric furnaces to develop the steel ingot and cast steel product manufacturing business and has an integrated production system from materials to processing.

Headquarters: 1083 Tsuneishi, Numakuma-cho, Fukuyama, Hiroshima, Japan
Representative: SHIMOMURA Naoya, President
Website: https://www.tsuneishi.co.jp/iron-w/

For further information, please contact:
Corporate Communications Dept.
TSUNEISHI GROUP CORPORATION
Email: pr@tsuneishi.com