CSTM

Constellium SE Cross-source read$25.55 2.44%
MaterialsCUSIP F21107101· EOD Sep 18, 2026

Among active 13F managers last quarter, 4 opened and 28 added, while 28 reduced; the largest holder to move was Millennium Management LLC (−45%). Over the last 180 days, 10 insiders sold and 2 insiders bought, a net -$6.2M in open-market trades.

Tracked 13F holders
341
191 in Q2 2026 filings
13F value (tracked)
$2.9B
Smart-money readMixed
Net sellingNet buying
Funds · active managers, latest 13F
32 adding · 28 trimming
Insiders · Form 4 open-market, 180d
2 buying · 10 selling · -$6.2M
US House · STOCK Act, 180d
0 buying · 0 selling

The legs disagree, or only one of them leans.

Price & smart-money activity

$25.55 2.44%5Y +31.3%
$6.11$14.10$22.09$30.07$38.06202120222023202420252026252424323429362741283139294229343433353749346529604553526740585667526865415103652118848
Hover for who · click for detailEnd-of-day closing prices52w $14.41 – $36.15

Who owns CSTM?

341 tracked 13F filers · ranked by shares held

341 tracked 13F filers disclose a position in CSTM as of the latest SEC 13F filings, a combined $2.9B in reported value. Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership.

#FundSharesPosition valueLast moveAs ofHistory
1BlackRock, Inc.12.8M
$408.0M
−1.2%
Reduced · −162K sh
Q2 2026
2Bpifrance SA8.4M
$267.8M
−33%
Reduced · −4.2M sh
Q2 2026
3Vanguard Portfolio Management LLC4.4M
$140.0M
+12%
Added · +465K sh
Q2 2026
4Millennium Management LLC3.5M
$85.3M
−45%
Reduced · −2.8M sh
Q1 2026
5D. E. Shaw & Co., Inc.3.2M
$79.5M
+5.9%
Added · +179K sh
Q1 2026
6Arrowstreet Capital, Limited Partnership3.2M
$79.3M
+621%
Added · +2.8M sh
Q1 2026
7Morgan Stanley3.2M
$78.6M
−14%
Reduced · −532K sh
Q1 2026
8T. Rowe Price Investment Management, Inc.3.0M
Withheld
−25%
Reduced · −980K sh
Q2 2026
9State Street Corp3.0M
$94.2M
+6.9%
Added · +191K sh
Q2 2026
10Nuveen, LLC2.8M
$69.5M
−0.5%
Reduced · −13K sh
Q1 2026
11Kinetic Partners Management, LP2.5M
$81.0M
+94%
Added · +1.2M sh
Q2 2026
12Encompass Capital Advisors LLC2.4M
$77.2M
−2.3%
Reduced · −56K sh
Q2 2026
13AllianceBernstein L.P.2.3M
$43.7M
17×
Added · +2.2M sh
Q1 2026
14FMR LLC2.2M
$69.9M
−68%
Reduced · −4.8M sh
Q2 2026
15American Century Companies Inc2.1M
$51.3M
+15%
Added · +274K sh
Q1 2026
16AQR Capital Management LLC2.1M
$51.0M
+17%
Added · +308K sh
Q1 2026
17Healthcare Of Ontario Pension Plan Trust Fund2.1M
$50.5M
+894%
Added · +1.8M sh
Q1 2026
18JPMorgan Chase & Co2.1M
$47.3M
−1.8%
Reduced · −37K sh
Q1 2026
19Brightline Capital Management, LLC1.9M
$61.3M
+4.1%
Added · +76K sh
Q2 2026
20Geode Capital Management, LLC1.8M
$57.0M
+7.3%
Added · +121K sh
Q2 2026
21Goldman Sachs Group Inc1.4M
$33.7M
+0.3%
Added · +4K sh
Q1 2026
22Westwood Holdings Group Inc1.1M
$35.0M
−22%
Reduced · −302K sh
Q2 2026
23Panagora Asset Management Inc1.0M
$33.4M
+49%
Added · +343K sh
Q2 2026
24Northern Trust Corp978K
$24.0M
+3.8%
Added · +36K sh
Q1 2026
25Allianz Asset Management GmbH894K
$22.0M
+408%
Added · +718K sh
Q1 2026

Holders and values reflect the 13F filers Arkolith currently tracks, not the entire institutional universe. Counts and totals are a floor, not the full institutional ownership. 3 value rows are withheld because the reported units disagree with same-security peers; share counts are unchanged.

Is CSTM being bought or sold by institutions?

Last quarter, 4 funds opened a new position in CSTM and 28 added to an existing one, while 28 reduced. Based on 13F filings from active, signal-eligible managers (passive index funds and other mechanical holders are excluded from this count).

Opened
4
funds took a first position
Added
28
added to an existing position
Reduced
28
reduced, still holding
Biggest moves · ranked by size of the change, positions above a floor

Funds that own CSTM also own

CompanyCo-held byTheir position there
Amazon.com IncAMZN194 funds$180.8B
Microsoft CorpMSFT193 funds$225.4B
Nvidia CorpNVDA189 funds$356.3B
Meta Platforms Inc-Class AMETA183 funds$96.3B
Alphabet Inc-CL CGOOG181 funds$107.2B
Apple IncAAPL180 funds$256.7B
Alphabet Inc-CL AGOOGL180 funds$161.3B
Eli Lilly & CoLLY177 funds$74.0B
JPMorgan Chase & CoJPM177 funds$57.7B
Micron Technology IncMU177 funds$47.5B
Advanced Micro DevicesAMD177 funds$47.2B
Broadcom IncAVGO174 funds$149.0B

Ranked by how many of CSTM's tracked holders also hold each name. The last column is those co-holders' combined reported position in that name, not in CSTM.

Insider activity (Form 4)

Full insider page →
Buys · 180d
$166K
2 insiders
Sells · 180d
$6.4M
10 insiders
Net · 180d
-$6.2M
14 open-market transactions
DateInsiderRoleActionSharesValue
Aug 3, 2026Deslarzes Jean-ChristopheDirectorBuy (P)1K$41K
Jun 4, 2026Ormerod JohnDirectorSell (S)8K$280K
May 28, 2026Becker MarcusSVP CPOSell (S)10K$363K
May 14, 2026Soultz Bradley LeeDirectorBuy (P)3K$85K
May 14, 2026Jarrett MartinSVP Chief Innovation OfficerSell (S)5K$158K
May 12, 2026Piquier LudovicSVP Manuf Excellence & CTOSell (S)1K$34K
May 11, 2026Brun NicolasSVP PA, Comm & SustSell (S)27K$902K
May 8, 2026Corre StephanePresident, AS&ISell (S)5K$168K
May 5, 2026Brandjes MichielDirectorSell (S)10K$325K
May 5, 2026Guo Jack Q.EVP & CFOSell (S)25K$822K
May 1, 2026Deslarzes Jean-ChristopheDirectorBuy (P)1K$41K
May 1, 2026Corre StephanePresident, AS&ISell (S)5K$160K

Do institutions, insiders and Congress agree?

Mixed signals

Where institutional funds (13F), corporate insiders (Form 4) and US House members (STOCK Act) are buying or selling the same name in the same window. Green is buying, red is selling.

SEC EDGAR 13F + Form 4 + US House STOCK Act{ }get_ticker_confluence · API & MCP

Signals by source

Insiders and Congress: last 180 days. Funds: latest 13F, top 100 holders incl. passive

SourceBuyingSellingNet
13F funds
Top 100 holders by value, passive included; the hero counts active managers only
5141
Insiders
Form 4 open-market
210-$6.2M
US House
STOCK Act trades
00$0
Sector rotation
CSTM is in Materials, which smart money is rotating OUT OF
$5.3B

Capital Rotation reports where institutional capital disclosed rotating, as of the latest public SEC 13F filings. It is data, not investment advice, a recommendation, or a prediction. Filings lag about 45 days and cover long US equity positions only. Past disclosed flows do not indicate future prices. Do your own research; consult a licensed advisor.

Institutional ownership over time

191 tracked filers in Q2 2026 filingsstill filing
0139278Q3 2024Q1 2025Q3 2025Q1 2026Q2 2026
tracked filers holding their reported valueQ2 2026 filings so far: $853.1M · 1 values withheld
Each bar counts tracked filers with a position in that quarter's filings, so the newest bar excludes filers still on an earlier quarter. Arkolith's tracked universe has grown over this window; part of any long-run rise is coverage, not new buyers.

Recent filings

15 most recent

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Connected entities for CSTM

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Ask your agent what changed in CSTM

This stock page is the public Follow view. For one current, evidence-backed answer, use capital_change_brief through REST or MCP. It compares tracked 13F changes with qualifying Form 4 activity and cites the SEC evidence.

Copy-paste
curl -H "Authorization: Bearer YOUR_API_KEY" \
  "https://arkolith.com/api/v1/stocks/CSTM/capital-change-brief"
Ask your agent
Use Arkolith's capital_change_brief for CSTM.
Tell me what changed, whether insider activity
corroborates it, and cite the SEC evidence.

13F holdings + Form 4 insider transactions + end-of-day price history + the live filing stream, joined for CSTM. Filings are public domain, sourced to SEC EDGAR; price series derived from end-of-day closes.