Tenaris S.A.

Transaction in Own Shares • Dec 20, 2024

Giovanni Sardagna Tenaris 1-888-300-5432 www.tenaris.com

Weekly Report (December 16, 2024 – December 20, 2024) on the USD 700 million Tenaris Share Buyback Program.

Luxembourg, December 20, 2024. - Tenaris S.A. (NYSE and Mexico: TS and EXM Italy: TEN) ("Tenaris") announced today that pursuant to its up to USD 700 million Share Buyback Program announced on November 10, 2024, (subject to a maximum of 46,373,915 ordinary shares), to be executed in the open market, it has repurchased the following ordinary shares from December 16, 2024 to (and including) December 20, 2024:

Date	Trading Venue	Shares Purchased	Weighted Average Price (EUR)	Purchases in EUR	Reference FX	Purchases in USD
16-dic-24	MTAA	334,492	18.3334	6,132,376	1.0506	6,442,674
17-dic-24	MTAA	863,754	18.1048	15,638,093	1.0498	16,416,870
17-dic-24	CEUX	416,987	18.1029	7,548,674	1.0498	7,924,598
17-dic-24	TQEX	70,000	18.1055	1,267,385	1.0498	1,330,501
17-dic-24	AQEU	60,000	18.1055	1,086,330	1.0498	1,140,429
18-dic-24	MTAA	100,000	18.1838	1,818,380	1.0472	1,904,208
19-dic-24	MTAA	583,779	18.0333	10,527,462	1.0379	10,926,453
19-dic-24	CEUX	200,000	18.0313	3,606,260	1.0379	3,742,937
20-dic-24	MTAA	664,000	17.8366	11,843,502	1.0398	12,314,282
20-dic-24	CEUX	259,023	17.8144	4,614,339	1.0398	4,797,759
20-dic-24	TQEX	43,385	17.8092	772,652	1.0398	803,365
20-dic-24	AQEU	37,417	17.8390	667,482	1.0398	694,014
		3,632,837	18.0363	65,522,936		68,438,090

From December 16, 2024 to (and including) December 20, 2024, the Company has purchased a total of 3,632,837 ordinary shares for a total consideration of €65,522,936, equivalent to USD68,438,090.

As of December 20, 2024, the Company held in treasury 77,416,706 ordinary shares (including 53,900,466 ordinary shares bought pursuant to the USD 1.2 billion Share Buyback Program), equal to 6.66% of the total issued share capital.

Tenaris intends to cancel treasury shares purchased under the Programs in due course.

Details of the above transactions, are available on Tenaris's corporate website under the Share Buyback Program Section https://ir.tenaris.com/share-buyback-program.

Some of the statements contained in this press release are "forward-looking statements". Forward-looking statements are based on management's current views and assumptions and involve known and unknown risks that could cause actual results, performance or events to differ materially from those expressed or implied by those statements. These risks include but are not limited to risks arising from uncertainties as to future oil and gas prices and their impact on investment programs by oil and gas companies.

Tenaris is a leading global supplier of steel tubes and related services for the world's energy industry and certain other industrial applications.