|
Company
|
Country of Incorporation
|
Main activity
|
Percentage of ownership at December 31, (*)
|
|
2025
|
2024
|
2023
|
|
ALGOMA TUBES INC.
|
Canada
|
Manufacturing of welded and seamless steel pipes
|
100%
|
100%
|
100%
|
|
CONFAB INDUSTRIAL S.A. and subsidiaries
|
Brazil
|
Manufacturing of welded steel pipes
|
100%
|
100%
|
100%
|
|
DALMINE S.p.A. and subsidiaries (a)
|
Italy
|
Manufacturing of seamless steel pipes
|
100%
|
100%
|
100%
|
|
EXIROS B.V. and subsidiaries (b)
|
Netherlands
|
Procurement and trading services
|
50%
|
50%
|
50%
|
|
HYDRIL COMPANY
|
USA
|
Manufacturing and marketing of premium connections
|
100%
|
100%
|
100%
|
|
MAVERICK TUBE CORPORATION and subsidiaries
|
USA
|
Manufacturing of welded and seamless steel pipes
|
100%
|
100%
|
100%
|
|
OILFIELD SERVICES SOCIEDAD ANONIMA
|
Argentina
|
Hydraulic fracturing and coiled tubing services
|
100%
|
100%
|
100%
|
|
P.T. SEAMLESS PIPE INDONESIA JAYA
|
Indonesia
|
Manufacturing of seamless steel products
|
89%
|
89%
|
89%
|
|
SILCOTUB S.A.
|
Romania
|
Manufacturing of seamless steel pipes
|
100%
|
100%
|
100%
|
|
SAUDI STEEL PIPE CO. and subsidiaries (c)
|
Saudi Arabia
|
Manufacturing of welded steel pipes
|
48%
|
48%
|
48%
|
|
SIAT SOCIEDAD ANONIMA
|
Argentina
|
Manufacturing of welded steel pipes
|
100%
|
100%
|
100%
|
|
SIDERCA SOCIEDAD ANONIMA INDUSTRIAL Y COMERCIAL and subsidiaries (d)
|
Argentina
|
Manufacturing of seamless steel pipes
|
100%
|
100%
|
100%
|
|
TALTA - TRADING E MARKETING SOCIEDADE UNIPESSOAL LDA.
|
Portugal
|
Holding company
|
100%
|
100%
|
100%
|
|
TENARIS BAY CITY, INC.
|
USA
|
Manufacturing of welded and seamless steel pipes
|
100%
|
100%
|
100%
|
|
TENARIS CONNECTIONS BV
|
Netherlands
|
Development, management and licensing of intellectual property
|
100%
|
100%
|
100%
|
|
TENARIS GLOBAL SERVICES (CANADA) INC.
|
Canada
|
Marketing of steel products
|
100%
|
100%
|
100%
|
|
TENARIS GLOBAL SERVICES (U.S.A.) CORPORATION
|
USA
|
Marketing of steel products
|
100%
|
100%
|
100%
|
|
TENARIS GLOBAL SERVICES (UK) LTD
|
United Kingdom
|
Holding company and marketing of steel products
|
100%
|
100%
|
100%
|
|
TENARIS GLOBAL SERVICES S.A. and subsidiaries
|
Uruguay
|
Marketing, distribution of steel products and holding company
|
100%
|
100%
|
100%
|
|
TENARIS INVESTMENTS (NL) B.V. and subsidiaries
|
Netherlands
|
Holding company
|
100%
|
100%
|
100%
|
|
TENARIS GLOBAL SERVICES and INVESTMENTS S.àr.l. and subsidiaries
|
Luxembourg
|
Marketing and distribution of steel products, financial operations and holding company
|
100%
|
100%
|
100%
|
|
TENARIS QINGDAO STEEL PIPES LTD.
|
China
|
Processing of premium joints, couplings and automotive components
|
100%
|
100%
|
100%
|
|
TENARIS TUBOCARIBE LTDA.
|
Colombia
|
Manufacturing of welded and seamless steel pipes
|
100%
|
100%
|
100%
|
|
TUBOS DE ACERO DE MEXICO, S.A. and subsidiaries
|
Mexico
|
Manufacturing of seamless steel pipes
|
100%
|
100%
|
100%
|