CSTM · Constellium SE · Shareholders & Ownership

$23.22 -0.77 (-3.21%) At close · Oct 23

Russell 2000 member Rebalance outlook locked

Market Cap

$3.16B

136.15M

Volume · Oct 23 1.5M Avg daily vol (3M) 1.51M

Every disclosed holder of CSTM in one list: 13F institutions, Schedule 13D and 13G filers, insiders (Forms 3, 4 and 5) and registered funds, each from its own latest filing. Holders nest by CIK and SEC reporting links, never by name, and each is summed once.

How the holder list picks a filing →

Who Owns CSTM

13F quarter Sep 30, 2026, combined view: filers that have not filed yet carry their Jun 30, 2026 positions

Holder group	Holders	Shares	% Out	Summed
Institutional (13F)	383	119,750,301	87.95%	Yes
Insiders (Forms 3, 4, 5)	22	1,866,482	1.37%	Yes
13D/G-only blocks	0	0	0.00%	Yes
Remaining	—	14,533,667	10.67%	Rest
Registered funds (N-PORT, not summed)	107	13,816,490	10.15%	No

Shares outstanding: 136,150,450, the issuer's latest cover-page count restated onto today's split basis.

13D/G-only counts each filer's latest 13D or 13G that no 13F report of the listing contains, that names no 13F filer and that no counted insider files. Funds are never summed: their shares sit inside their advisers' 13F reports.

Holders of CSTM

One row per holder Every filing By ultimate parent

All 13F Funds Insiders 13D/G Non-US

#	Holder	Shares	% Out	Change	As of	Notes
1	BlackRock, Inc. 13F CIK 2012383 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	12,802,322	9.40%	-161,881	Jun 30, 2026	carried, not yet filed for the newest quarter
1.1	iShares MSCI Global Metals & Mining Producers ETF Fund S000035885 · Registered fund · May 31, 2026 iShares, Inc., not summed	156,930	0.12%	+4,266	May 31, 2026	iShares, Inc., not summed
1.2	iShares ESG Aware MSCI USA Small-Cap ETF Fund S000061604 · Registered fund · Aug 31, 2026 iShares Trust, not summed	109,454	0.08%	+20,027	Aug 31, 2026	iShares Trust, not summed
1.3	iShares US Small Cap Value Factor ETF Fund S000069740 · Registered fund · Jun 30, 2026 iShares Trust, not summed	24,351	0.02%	-21,207	Jun 30, 2026	iShares Trust, not summed
1.4	iShares MSCI World Small-Cap ETF Fund S000091430 · Registered fund · Aug 31, 2026 iShares Trust, not summed	7,150	0.01%	0	Aug 31, 2026	iShares Trust, not summed
2	Bpifrance SA 13F CIK 1731118 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	8,403,903	6.17%	-4,190,000	Jun 30, 2026	carried, not yet filed for the newest quarter
3	MORGAN STANLEY 13F CIK 895421 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	6,183,255	4.54%	+2,987,201	Jun 30, 2026	carried, not yet filed for the newest quarter
4	VANGUARD PORTFOLIO MANAGEMENT LLC 13F CIK 2100121 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	4,391,756	3.23%	+464,659	Jun 30, 2026	carried, not yet filed for the newest quarter
5	AMERICAN CENTURY COMPANIES INC 13F CIK 748054 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	4,220,743	3.10%	+2,135,264	Jun 30, 2026	carried, not yet filed for the newest quarter
5.1	Small Cap Growth Fund Fund S000006193 · Registered fund · Jul 31, 2026 American Century Mutual Funds, Inc., not summed	1,114,924	0.82%	—	Jul 31, 2026	American Century Mutual Funds, Inc., not summed
5.2	Small Company Fund Fund S000005981 · Registered fund · Jun 30, 2026 American Century Quantitative Equity Funds, Inc., not summed	25,242	0.02%	-1,964	Jun 30, 2026	American Century Quantitative Equity Funds, Inc., not summed
6	T. Rowe Price Investment Management, Inc. 13F CIK 1897612 · Investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	2,980,566	2.19%	-980,253	Jun 30, 2026	carried, not yet filed for the newest quarter
7	STATE STREET CORP 13F CIK 93751 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	2,954,799	2.17%	+191,304	Jun 30, 2026	carried, not yet filed for the newest quarter
8	ARROWSTREET CAPITAL, LIMITED PARTNERSHIP 13F CIK 1164508 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	2,844,747	2.09%	-383,280	Jun 30, 2026	carried, not yet filed for the newest quarter
9	Nuveen, LLC 13F CIK 1871926 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	2,770,828	2.04%	-56,903	Jun 30, 2026	carried, not yet filed for the newest quarter
9.1	College Retirement Equities Fund - Total Global Stock Account Fund S000005080 · Registered fund · Jun 30, 2026 College Retirement Equities Fund, not summed	1,093,148	0.80%	-38,310	Jun 30, 2026	College Retirement Equities Fund, not summed
9.2	Nuveen Quant Small Cap Equity Fund Fund S000005386 · Registered fund · Jul 31, 2026 TIAA-CREF Funds, not summed	674,970	0.50%	-13,360	Jul 31, 2026	TIAA-CREF Funds, not summed
9.3	Nuveen Quant Small/Mid Cap Equity Fund Fund S000054623 · Registered fund · Jul 31, 2026 TIAA-CREF Funds, not summed	451,759	0.33%	0	Jul 31, 2026	TIAA-CREF Funds, not summed
9.4	Nuveen Small Cap Blend Index Fund Fund S000005367 · Registered fund · Jul 31, 2026 TIAA-CREF Funds, not summed	175,096	0.13%	+10,316	Jul 31, 2026	TIAA-CREF Funds, not summed
9.5	Nuveen Equity Index Fund Fund S000005360 · Registered fund · Jul 31, 2026 TIAA-CREF Funds, not summed	127,159	0.09%	0	Jul 31, 2026	TIAA-CREF Funds, not summed
10	Kinetic Partners Management, LP 13F CIK 1911448 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	2,542,400	1.87%	+1,230,000	Jun 30, 2026	carried, not yet filed for the newest quarter
11	Encompass Capital Advisors LLC 13F CIK 1541901 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	2,421,349	1.78%	-55,929	Jun 30, 2026	carried, not yet filed for the newest quarter
12	AQR CAPITAL MANAGEMENT LLC 13F CIK 1167557 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	2,402,937	1.76%	+328,076	Jun 30, 2026	carried, not yet filed for the newest quarter
13	HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND 13F CIK 1535845 · Non-US institution · Jun 30, 2026 carried, not yet filed for the newest quarter	2,278,202	1.67%	+221,866	Jun 30, 2026	carried, not yet filed for the newest quarter
14	D. E. Shaw & Co., Inc. 13F CIK 1009207 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	2,198,618	1.61%	-1,035,958	Jun 30, 2026	carried, not yet filed for the newest quarter
15	FMR LLC 13F CIK 315066 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	2,194,722	1.61%	-4,767,046	Jun 30, 2026	carried, not yet filed for the newest quarter
15.1	FMR LLC 13G CIK 315066 · Holding company · Jun 30, 2026 Rule 13d-1(b), qualified institution, not summed	2,194,722	1.61%	-4,767,045	Jun 30, 2026	Rule 13d-1(b), qualified institution, not summed
16	ALLIANCEBERNSTEIN L.P. 13F CIK 1109448 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	2,162,231	1.59%	-154,777	Jun 30, 2026	carried, not yet filed for the newest quarter
17	ACADIAN ASSET MANAGEMENT LLC 13F CIK 916542 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	2,107,513	1.55%	+834,642	Jun 30, 2026	carried, not yet filed for the newest quarter
18	GOLDMAN SACHS GROUP INC 13F CIK 886982 · Holding company · Jun 30, 2026 carried, not yet filed for the newest quarter	2,070,665	1.52%	+698,889	Jun 30, 2026	carried, not yet filed for the newest quarter
19	MILLENNIUM MANAGEMENT LLC 13F CIK 1273087 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	1,956,365	1.44%	-1,513,726	Jun 30, 2026	carried, not yet filed for the newest quarter
20	BRIGHTLINE CAPITAL MANAGEMENT, LLC 13F CIK 1432450 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	1,923,000	1.41%	+76,000	Jun 30, 2026	carried, not yet filed for the newest quarter
21	Avantis International Small Cap Value ETF Fund S000066457 · Registered fund · May 31, 2026 American Century ETF Trust, not summed	1,875,744	1.38%	+455,686	May 31, 2026	American Century ETF Trust, not summed
22	NOMURA ASSET MANAGEMENT INTERNATIONAL INC. 13F CIK 921739 · Investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	1,856,018	1.36%	-57,415	Jun 30, 2026	carried, not yet filed for the newest quarter
23	GEODE CAPITAL MANAGEMENT, LLC 13F CIK 1214717 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	1,789,723	1.31%	+121,272	Jun 30, 2026	carried, not yet filed for the newest quarter
24	Allianz Asset Management GmbH 13F CIK 1535323 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	1,453,717	1.07%	+559,780	Jun 30, 2026	carried, not yet filed for the newest quarter
25	SG Americas Securities, LLC 13F CIK 1313360 · Non-US institution · Jun 30, 2026 carried, not yet filed for the newest quarter	1,234,038	0.91%	-263,422	Jun 30, 2026	carried, not yet filed for the newest quarter
26	VANGUARD STRATEGIC EQUITY FUND Fund S000002593 · Registered fund · Jun 30, 2026 VANGUARD HORIZON FUNDS, not summed	1,210,699	0.89%	+127,941	Jun 30, 2026	VANGUARD HORIZON FUNDS, not summed
27	JPMORGAN CHASE & CO 13F CIK 19617 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	1,146,089	0.84%	-905,841	Jun 30, 2026	carried, not yet filed for the newest quarter
28	WESTWOOD HOLDINGS GROUP INC 13F CIK 1165002 · Investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	1,099,362	0.81%	-302,054	Jun 30, 2026	carried, not yet filed for the newest quarter
29	MARSHALL WACE, LLP 13F CIK 1318757 · Exempt reporting adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	1,093,740	0.80%	+1,079,965	Jun 30, 2026	carried, not yet filed for the newest quarter
30	Senator Investment Group LP 13F CIK 1443689 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	1,083,489	0.80%	+1,083,489	Jun 30, 2026	carried, not yet filed for the newest quarter
31	PANAGORA ASSET MANAGEMENT INC 13F CIK 883677 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	1,048,331	0.77%	+343,491	Jun 30, 2026	carried, not yet filed for the newest quarter
32	NORTHERN TRUST CORP 13F CIK 73124 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	984,446	0.72%	+6,863	Jun 30, 2026	carried, not yet filed for the newest quarter
32.1	Small Cap Index Fund Fund S000001245 · Registered fund · Jun 30, 2026 Northern Funds, not summed	68,621	0.05%	+5,299	Jun 30, 2026	Northern Funds, not summed
32.2	Small Cap Core Fund Fund S000001244 · Registered fund · Jun 30, 2026 Northern Funds, not summed	16,303	0.01%	-465	Jun 30, 2026	Northern Funds, not summed
32.3	Multi-Manager High Yield Opportunity Fund Fund S000026479 · Registered fund · Jun 30, 2026 Northern Funds, not summed	2,080	0.00%	-1,604	Jun 30, 2026	Northern Funds, not summed
33	BANK OF AMERICA CORP /DE/ 13F CIK 70858 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	957,579	0.70%	+106,357	Jun 30, 2026	carried, not yet filed for the newest quarter
34	VANGUARD EXPLORER FUND Fund S000002578 · Registered fund · Jul 31, 2026 VANGUARD EXPLORER FUND, not summed	885,343	0.65%	+113,468	Jul 31, 2026	VANGUARD EXPLORER FUND, not summed
35	WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC 13F CIK 1644956 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	882,306	0.65%	-35,784	Jun 30, 2026	carried, not yet filed for the newest quarter
36	HRT FINANCIAL LP 13F CIK 1475597 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	874,136	0.64%	+355,304	Jun 30, 2026	carried, not yet filed for the newest quarter
37	FEDERATED HERMES, INC. 13F CIK 1056288 · Investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	838,604	0.62%	+185,946	Jun 30, 2026	carried, not yet filed for the newest quarter
38	Point72 Asset Management, L.P. 13F CIK 1603466 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	821,701	0.60%	-183,502	Jun 30, 2026	carried, not yet filed for the newest quarter
39	BEACONLIGHT CAPITAL, LLC 13F CIK 1569537 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	779,899	0.57%	-391,913	Jun 30, 2026	carried, not yet filed for the newest quarter
40	Penn Capital Management Company, LLC 13F CIK 1158202 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	749,645	0.55%	-95,289	Jun 30, 2026	carried, not yet filed for the newest quarter
41	CHARLES SCHWAB INVESTMENT MANAGEMENT INC 13F CIK 884546 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	734,247	0.54%	-48,990	Jun 30, 2026	carried, not yet filed for the newest quarter
42	VANGUARD RUSSELL 2000 INDEX FUND Fund S000030003 · Registered fund · May 31, 2026 VANGUARD SCOTTSDALE FUNDS, not summed	705,025	0.52%	+25,001	May 31, 2026	VANGUARD SCOTTSDALE FUNDS, not summed
43	Bayberry Capital Partners LP 13F CIK 1771524 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	655,000	0.48%	-219,000	Jun 30, 2026	carried, not yet filed for the newest quarter
44	DANSKE BANK A/S 13F CIK 800177 · Bank · Jun 30, 2026 carried, not yet filed for the newest quarter	642,706	0.47%	+247,266	Jun 30, 2026	carried, not yet filed for the newest quarter
45	Balyasny Asset Management L.P. 13F CIK 1218710 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	641,403	0.47%	-154,010	Jun 30, 2026	carried, not yet filed for the newest quarter
46	Qube Research & Technologies Ltd 13F CIK 1729829 · Exempt reporting adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	622,121	0.46%	+151,192	Jun 30, 2026	carried, not yet filed for the newest quarter
47	MACKENZIE FINANCIAL CORP 13F CIK 919859 · Registered investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	592,538	0.44%	+411,068	Jun 30, 2026	carried, not yet filed for the newest quarter
48	Fisher Asset Management, LLC 13F CIK 850529 · Investment adviser · Jun 30, 2026 carried, not yet filed for the newest quarter	552,416	0.41%	+12,965	Jun 30, 2026	carried, not yet filed for the newest quarter
49	NEW YORK STATE COMMON RETIREMENT FUND 13F CIK 810265 · Unknown · Jun 30, 2026 carried, not yet filed for the newest quarter	520,203	0.38%	-49,984	Jun 30, 2026	carried, not yet filed for the newest quarter
50	VANGUARD STRATEGIC SMALL-CAP EQUITY FUND Fund S000012432 · Registered fund · Jun 30, 2026 VANGUARD HORIZON FUNDS, not summed	512,534	0.38%	0	Jun 30, 2026	VANGUARD HORIZON FUNDS, not summed

4 more nested rows are not shown here; Every filing lists them all.

Shares are restated onto today's split basis. Change compares each row with the same holder's previous filing in the same source; a dash means there is none to compare. Nested 13D/G, insider and fund rows are not summed, since a 13F report already holds them.

Showing 1–50 of 477 holders

Create a free account to page through every holder, filter by source and group by ultimate parent.

Key facts CIK 1563411 CUSIP F21107101 13F (30d) 47 filings 47 filers Visit website Investor relations