Company: TNRSF
Filing Date: 2025-02-21
Form Type: 6-K
Source: 0001171843-25-000987
Chunk: 21

Company: TENARIS SA
Filing Date: 2025-02-21
Form: 6-K
Chunk 21
---
.

Management’s re-estimation of assets useful lives, performed in accordance
with IAS 38, did not materially affect amortization expenses for the years 2024, 2023 and 2022.

| (3) | Licenses, patents, trademarks and proprietary technology |

Licenses, patents, trademarks, and proprietary technology are initially
recognized at cost, or at fair value at the acquisition date in case of a business combination. Licenses, patents, proprietary technology
and those trademarks that have a finite useful life are carried at cost less accumulated amortization. Amortization is calculated using
the straight-line method to allocate the cost over their estimated useful lives, which are in the range between 3 and 20 years. Amortization
charges are mainly classified as Cost of sales in the Consolidated Income Statement.

The balance of acquired trademarks that have indefinite useful lives according
to external appraisal amounts to $86.7 million at December 31, 2024, 2023 and 2022, and are included
in Hydril CGU. Main factors considered in the determination of the indefinite useful lives include the years that they have been in service
and their recognition among customers in the industry.

Management’s re-estimation of assets useful lives, performed in accordance
with IAS 38, did not materially affect amortization expenses for the years 2024, 2023 and 2022.

| (4) | Research and development |

Research expenditures as well as development costs that do not fulfill
the criteria for capitalization are recorded as Cost of sales in the Consolidated Income Statement as incurred. Research and development
expenditures included in Cost of sales for the years 2024, 2023 and 2022 totaled $74.2 million,
$60.0 million and $50.7 million, respectively.

Capitalized costs were not material for the years 2024, 2023 and 2022.

| (5) | Customer relationships |

In accordance with IFRS 3, "Business Combinations"
and IAS 38, Tenaris has recognized the value of customer relationships separately from goodwill attributable to the acquisition of Maverick
Tube Corporation (“Maverick”) and Hydril Company (“Hydril”) groups, Saudi Steel Pipe Co. (“SSPC”),
Ipsco Tubulars Inc. (“IPSCO”) and the more recent acquisition of Mattr’s pipe coating business unit.

Customer relationships acquired in a business combination