Tenaris S.A.

Transaction in Own Shares • Nov 13, 2023

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

Weekly Report (November 6, 2023- November 10, 2023) on the First Tranche of Tenaris Share Buyback Program

Luxembourg, November 13, 2023. - Tenaris S.A. (NYSE and Mexico: TS and EXM Italy: TEN) ("Tenaris") announced today that pursuant to its First Tranche of the Share Buyback Program announced on November 5, 2023, covering up to \$300 million to be executed in the open market, it has repurchased the following ordinary shares from November 6 to ( and including) November 10, 2023:

Date	Trading Venue	Shares Purchased	Weighted Average Price (EUR)	Purchases in EUR	Reference FX	Purchases in USD
6-Nov-23	MTA	338,793	16.6222	5,631,485	1.07335	6,044,554
7-Nov-23	MTA	602,507	16.3430	9,846,772	1.07445	10,579,864
7-Nov-23	CEUX	285,803	16.2387	4,641,069	1.07445	4,986,597
7-Nov-23	TQEX	666	16.2100	10,796	1.07445	11,600
7-Nov-23	AQXE	28,002	16.2373	454,677	1.07445	488,528
8-Nov-23	MTA	279,666	15.7534	4,405,690	1.06850	4,707,480
9-Nov-23	MTA	571,658	15.8704	9,072,441	1.07065	9,713,409
9-Nov-23	CEUX	268,774	15.8698	4,265,390	1.07065	4,566,739
10-Nov-23	MTA	545,682	16.0932	8,781,742	1.07155	9,410,076
10-Nov-23	CEUX	259,919	16.0941	4,183,170	1.07155	4,482,476
	Total	3,181,470	16.1225	51,293,232		54,991,323

As of November 10, 2023, the Company held in treasury 3,181,470 ordinary shares equal to 0.27% of the total issued share capital.

Tenaris intends to cancel all shares purchased under the Program in due course.

Details of the above transactions, are available on Tenaris's corporate website under the Share Buyback Program Sectionhttps://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.