Company · Ownership research

TENARIS SA TS

CIK 0001190723 · CUSIP 88031M109

Insider tradingInitial holdingsInstitutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 88031M109 (TS), not CUSIP 88031M909 (TS), CUSIP 88031M959 (TS), CUSIP L90272136 (TNRSF), and does not merge CUSIPs.

This page lists the top 20 of 265 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	FMR LLC CIK 315066 · View history	$480.09M 8,251,759 shares	0.03%	+6.05M(+275.30%)Added	SEC filing ↗ May 15, 2026	▾
02	Westwood Global Investments, LLC CIK 1356513 · View history	$388.28M 6,673,718 shares	14.47%	-598.69K(-8.20%)Reduced	SEC filing ↗ May 14, 2026	▾
03	RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history	$186.16M 3,199,744 shares	0.29%	+235.40K(+7.90%)Added	SEC filing ↗ May 14, 2026	▾
04	VAN ECK ASSOCIATES CORP CIK 869178 · View history	$168.32M 2,893,032 shares	0.13%	+873.85K(+43.30%)Added	SEC filing ↗ May 15, 2026	▾
05	WELLINGTON MANAGEMENT GROUP LLP CIK 902219 · View history	$139.92M 2,405,034 shares	0.03%	-277.10K(-10.30%)Reduced	SEC filing ↗ May 15, 2026	▾
06	PRICE T ROWE ASSOCIATES INC /MD/ CIK 80255 · View history	$84.08M 1,445,210 shares	0.01%	-204.51K(-12.40%)Reduced	SEC filing ↗ May 15, 2026	▾
07	MORGAN STANLEY CIK 895421 · View history	$68.54M 1,178,069 shares	0.00%	+8.38K(+0.70%)Added	SEC filing ↗ May 15, 2026	▾
08	Invesco Ltd. CIK 914208 · Amended · View history	$67.98M 1,168,472 shares	0.01%	+622.27K(+113.90%)Added	SEC filing ↗ May 12, 2026	▾
09	DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history	$65.22M 1,121,007 shares	0.01%	-113.82K(-9.20%)Reduced	SEC filing ↗ May 7, 2026	▾
10	Driehaus Capital Management LLC CIK 938206 · View history	$51.68M 888,346 shares	0.38%	+888.35KNew	SEC filing ↗ May 15, 2026	▾
11	GOLDMAN SACHS GROUP INC CIK 886982 · View history	$41.94M 720,894 shares	0.01%	-98.68K(-12.00%)Reduced	SEC filing ↗ May 15, 2026	▾
12	BlackRock, Inc. CIK 2012383 · View history	$41.64M 715,791 shares	0.00%	+19.35K(+2.80%)Added	SEC filing ↗ May 13, 2026	▾
13	MASSACHUSETTS FINANCIAL SERVICES CO /MA/ CIK 912938 · View history	$38.08M 646,854 shares	0.01%	-9.59K(-1.50%)Reduced	SEC filing ↗ May 14, 2026	▾
14	CWA Asset Management Group, LLC CIK 1667134 · View history	$29.47M 506,550 shares	1.01%	+506.55KNew	SEC filing ↗ Apr 20, 2026	▾
15	UBS Group AG CIK 1610520 · View history	$29.03M 498,978 shares	0.01%	+276.25K(+124.00%)Added	SEC filing ↗ May 5, 2026	▾
16	ASSETMARK, INC CIK 1344551 · View history	$28.55M 490,777 shares	0.06%	-13.14K(-2.60%)Reduced	SEC filing ↗ May 6, 2026	▾
17	Grantham, Mayo, Van Otterloo & Co. LLC CIK 1352662 · View history	$20.22M 347,584 shares	0.05%	+15.35K(+4.60%)Added	SEC filing ↗ May 14, 2026	▾
18	Carrhae Capital LLP CIK 1555254 · View history	$19.63M 337,428 shares	1.39%	+337.43KNew	SEC filing ↗ May 14, 2026	▾
19	Harding Loevner LP CIK 928196 · View history	$17.04M 292,858 shares	0.18%	-18.42K(-5.90%)Reduced	SEC filing ↗ May 15, 2026	▾
20	CITADEL ADVISORS LLC CIK 1423053 · View history	$17.01M 292,423 shares	0.01%	-639.97K(-68.60%)Reduced	SEC filing ↗ May 15, 2026	▾

Showing 20 / 265 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

265

Cancelled or null records excluded

Disclosed shares

39,333,078

Not deduplicated across managers

Disclosed value

$2.29B

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

TENARIS SA · Q1 2026

Explore all 265 reporting institutions.

This page includes 20 of 265 reporting institutions. Log in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.