If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. Checkbox not checked

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).






SCHEDULE 13D




Comment for Type of Reporting Person:
Note to Row 4 (Source of funds): please refer to "Item 1 Comment" below. Note to Row 13 (Percent of class represented by amount in Row (11)): The percent of class figures set forth in this Amendment No. 12 are calculated based on 1,071,994,930 issued Ordinary Shares (as defined below), of which 29,499,198 were held by Tenaris S.A. as treasury stock as of September 12, 2025, as published on the website of Tenaris S.A.


SCHEDULE 13D




Comment for Type of Reporting Person:
Note to Row 4 (Source of funds): please refer to "Item 1 Comment" below. Note to Row 13 (Percent of class represented by amount in Row (11)): The percent of class figures set forth in this Amendment No. 12 are calculated based on 1,071,994,930 issued Ordinary Shares (as defined below), of which 29,499,198 were held by Tenaris S.A. as treasury stock as of September 12, 2025, as published on the website of Tenaris S.A.


SCHEDULE 13D




Comment for Type of Reporting Person:
Note to Row 4 (Source of funds): please refer to "Item 1 Comment" below. Note to Row 13 (Percent of class represented by amount in Row (11)): The percent of class figures set forth in this Amendment No. 12 are calculated based on 1,071,994,930 issued Ordinary Shares (as defined below), of which 29,499,198 were held by Tenaris S.A. as treasury stock as of September 12, 2025, as published on the website of Tenaris S.A.


SCHEDULE 13D


 
ROCCA & PARTNERS STICHTING ADMINISTRATIEKANTOOR AANDELEN SAN FAUSTIN
 
Signature:ROCCA & PARTNERS STICHTING ADMINISTRATIEKANTOOR AANDELEN SAN FAUSTIN
Name/Title:/s/ Fernando J. Mantilla / Attorney-in-fact
Date:09/19/2025
 
SAN FAUSTIN S.A.
 
Signature:SAN FAUSTIN S.A.
Name/Title:/s/ Fernando J. Mantilla / Attorney-in-fact
Date:09/19/2025
 
TECHINT HOLDINGS S.A R.L.
 
Signature:TECHINT HOLDINGS S.A R.L.
Name/Title:/s/ Fernando J. Mantilla / Attorney-in-fact
Date:09/19/2025
Comments accompanying signature:
Pursuant to Rule 13d-1(k)(1), the undersigned joins in the filing of this Amendment No. 12 on his own behalf and on behalf of SAN FAUSTIN S.A. and TECHINT HOLDINGS S.A R.L. Pursuant to Rule 13d-1(k)(1), the undersigned joins in the filing of this Amendment No. 12 on his own behalf and on behalf of ROCCA & PARTNERS STICHTING ADMINISTRATIEKANTOOR AANDELEN SAN FAUSTIN and TECHINT HOLDINGS S.A R.L. Pursuant to Rule 13d-1(k)(1), the undersigned joins in the filing of this Amendment No. 12 on his own behalf and on behalf of ROCCA & PARTNERS STICHTING ADMINISTRATIEKANTOOR AANDELEN SAN FAUSTIN and SAN FAUSTIN S.A.