# EDGAR Filing Document

**Accession Number:** 0001190723
**File Stem:** 0001213900-25-089522
**Filing Date:** 2025-9
**Character Count:** 14566
**Document Hash:** d9361e57527d02496388939d5ca755fb
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001213900-25-089522.hdr.sgml**: 20250919

**ACCESSION NUMBER**: 0001213900-25-089522

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13D/A

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20250919

**DATE AS OF CHANGE**: 20250919

**SUBJECT COMPANY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** TENARIS SA
- **CENTRAL INDEX KEY:** 0001190723
- **STANDARD INDUSTRIAL CLASSIFICATION:** STEEL WORKS, BLAST FURNACES  ROLLING MILLS (COKE OVENS) [3312]
- **ORGANIZATION NAME:** 04 Manufacturing
- **EIN:** 000000000

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-78699
- **FILM NUMBER:** 251326784

**BUSINESS ADDRESS:**
- **STREET 1:** 26, BOULEVARD ROYAL, 4TH FLOOR
- **CITY:** LUXEMBOURG
- **STATE:** N4
- **ZIP:** L-2449
- **BUSINESS PHONE:** 1-888-300-5432

**MAIL ADDRESS:**
- **STREET 1:** 26, BOULEVARD ROYAL, 4TH FLOOR
- **CITY:** LUXEMBOURG
- **STATE:** N4
- **ZIP:** L-2449
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** SAN FAUSTIN S.A.
- **CENTRAL INDEX KEY:** 0001429586

**ORGANIZATION NAME:**
- **EIN:** 000000000
- **STATE OF INCORPORATION:** N4
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A

**BUSINESS ADDRESS:**
- **STREET 1:** 26, BOULEVARD ROYAL, GROUND FLOOR
- **CITY:** LUXEMBOURG
- **STATE:** N4
- **ZIP:** L-2449
- **BUSINESS PHONE:** (352) 2720-9600

**MAIL ADDRESS:**
- **STREET 1:** 26, BOULEVARD ROYAL, GROUND FLOOR
- **CITY:** LUXEMBOURG
- **STATE:** N4
- **ZIP:** L-2449

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** San Faustin N.V.
- **DATE OF NAME CHANGE:** 20080312

### UNITED STATES SECURITIES AND EXCHANGE COMMISSION
**Washington, D.C. 20549**

## SCHEDULE 13D

### Under the Securities Exchange Act of 1934

**(Amendment No. 12)**

**Tenaris S.A.**

*(Name of Issuer)*

**Ordinary Shares, $1.00 par value per share**

*(Title of Class of Securities)*

**88031M109**

*(CUSIP Number)*

**Fernando J. Mantilla**<br>26, Boulevard Royal, Ground Floor,<br>Grand-Duchy of Luxembourg N4 L-2449<br>352 27209600

*(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)*

**09/17/2025**

*(Date of Event Which Requires Filing of this Statement)*

| **CUSIP No.** | **88031M109** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**ROCCA & PARTNERS STICHTING ADMINISTRATIEKANTOOR AANDELEN SAN FAUSTIN** | Name of reporting person<br>**ROCCA & PARTNERS STICHTING ADMINISTRATIEKANTOOR AANDELEN SAN FAUSTIN** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**P7** | Citizenship or place of organization<br>**P7** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**713605187.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**713605187.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**713605187.00** | Aggregate amount beneficially owned by each reporting person<br>**713605187.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**68.5%** | Percent of class represented by amount in Row (11)<br>**68.5%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**HC** | Type of Reporting Person (See Instructions)<br>**HC** | |

---

**Comment for 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.

| **CUSIP No.** | **88031M109** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**SAN FAUSTIN S.A.** | Name of reporting person<br>**SAN FAUSTIN S.A.** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**N4** | Citizenship or place of organization<br>**N4** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**713605187.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**713605187.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**713605187.00** | Aggregate amount beneficially owned by each reporting person<br>**713605187.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**68.5%** | Percent of class represented by amount in Row (11)<br>**68.5%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**CO** | Type of Reporting Person (See Instructions)<br>**CO** | |

---

**Comment for 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.

| **CUSIP No.** | **88031M109** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**TECHINT HOLDINGS S.A R.L.** | Name of reporting person<br>**TECHINT HOLDINGS S.A R.L.** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**N4** | Citizenship or place of organization<br>**N4** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**713605187.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**713605187.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**0.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**713605187.00** | Aggregate amount beneficially owned by each reporting person<br>**713605187.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**68.5%** | Percent of class represented by amount in Row (11)<br>**68.5%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**CO** | Type of Reporting Person (See Instructions)<br>**CO** | |

---

**Comment for 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.

**Item 1. Security and Issuer**

**(a) Title of Class of Securities:**
Ordinary Shares, $1.00 par value per share

**(b) Name of Issuer:**
Tenaris S.A.

**(c) Address of Issuer's Principal Executive Offices:**
26, BOULEVARD ROYAL, 4TH FLOOR, LUXEMBOURG, N4, L-2449

This Amendment No. 12 amends and supplements the Schedule 13D originally filed on February 14, 2011 (this "Amendment No. 12"), as further amended by Amendments No. 1, No. 2, No. 3, No. 4, No. 5, No. 6, No. 7, No. 8, No. 9, No. 10 and No. 11, on behalf of RP STAK, SAN FAUSTIN and TECHINT HOLDINGS (each as defined under Item 2 below) (collectively, the "Reporting Persons"), relating to the Ordinary Shares, par value $1 per share of Tenaris S.A. (the "Ordinary Shares"). This Amendment No. 12 reflects (i) the authorization given by SAN FAUSTIN's board of directors to TECHINT HOLDINGS to sell a number of its Ordinary Shares, provided that TECHINT HOLDINGS' ownership stake in Tenaris S.A. should not fall below 67 percent of the total outstanding Ordinary Shares (see Item 4 below) and (ii) an increase by 0.91% of the percent of class represented by the Ordinary Shares held by such Reporting Persons, from 67.54% to 68.45%, as reported on Rows 13 of the cover pages of this Schedule 13D, as a result of repurchases of Ordinary Shares made by Tenaris S.A. in the open market in the period from July 7, 2025 to September 12, 2025, under Tenaris S.A.'s 2025-2026 share buyback program publicly announced on May 27, 2025. Except as specifically provided herein, this Amendment No. 12 does not modify any of the information previously reported on the Schedule 13D and its amendments.

This Schedule 13D is being jointly filed by each of the Reporting Persons pursuant to Rule 13d-1(k).

**Item 4. Purpose of Transaction**

The last disclosure paragraph of the response set forth in Item 4 of the Schedule 13D originally filed on February 14, 2011, is hereby deleted in its entirety and replaced with the following:

For portfolio-management purposes and in response to Tenaris S.A.'s ongoing share repurchase program causing SAN FAUSTIN's beneficial ownership interest in Tenaris S.A. to passively increase, on September 17, 2025, the board of directors of SAN FAUSTIN authorized TECHINT HOLDINGS to sell a number of its Ordinary Shares, provided that TECHINT HOLDINGS' ownership stake in Tenaris S.A. should not fall below 67 percent of the total outstanding Ordinary Shares.  The precise timing, amount and manner of any such sales will depend upon market conditions and other factors, and there is no assurance that any sales will be completed or the timing thereof.  Although the Reporting Persons do not currently intend to purchase Ordinary Shares or to reduce their beneficial ownership below 67 percent of the total outstanding Ordinary Shares, they may from time to time, depending on market conditions and other factors, purchase or sell additional Ordinary Shares. Except as described in this Schedule 13D, the Reporting Persons do not have any present plans or proposals that relate to or would result in any of the actions described in subparagraphs (a) through (j) of Item 4 of Schedule 13D.

**Item 5. Interest in Securities of the Issuer**

**(a)**
RP STAK. See items (7) through (11) and (13) on page 2

SAN FAUSTIN. See items (7) through (11) and (13) on page 3

TECHINT HOLDINGS. See items (7) through (11) and (13) on page 4

**(b)**
RP STAK. See items (7) through (11) and (13) on page 2

SAN FAUSTIN. See items (7) through (11) and (13) on page 3

TECHINT HOLDINGS. See items (7) through (11) and (13) on page 4

**(c)**
During the last 60 days, there have been no transactions in Ordinary Shares effected by the Reporting Persons or, to the best of the Reporting Person's knowledge, any of the persons listed on Exhibit 99.1 to the Amendment No. 11 to the Schedule 13D of Tenaris S.A., filed on July 8, 2025.

### SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** 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

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** SAN FAUSTIN S.A.

**Signature:** SAN FAUSTIN S.A.

**Name/Title:** /s/ Fernando J. Mantilla / Attorney-in-fact

**Date:** 09/19/2025

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

**Reporting Person:** 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