CENTURY ALUM CO CENX
COM · Common Stock · CUSIP 156431108 · ISIN US1564311082
American aluminum manufacturer
- SectorMaterials
- IndustryPrimary Production of Aluminum
- HeadquartersChicago, IL
- Founded1995
- Websitecenturyaluminum.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($4.0m this quarter). Holder counts are more reliable. Shares outstanding: 99.0m as of 2026-08-04, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $46.01. Options: 21 managers hold calls ($148.5m notional), 13 hold puts ($46.6m).
Trends to Q2 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2022 | 176 |
| Q4 2022 | 169 |
| Q1 2023 | 169 |
| Q2 2023 | 161 |
| Q3 2023 | 163 |
| Q4 2023 | 172 |
| Q1 2024 | 181 |
| Q2 2024 | 192 |
| Q3 2024 | 198 |
| Q4 2024 | 223 |
| Q1 2025 | 219 |
| Q2 2025 | 223 |
| Q3 2025 | 256 |
| Q4 2025 | 326 |
| Q1 2026 | 387 |
| Q2 2026 | 414 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q3 2024 | 101 | 106 |
| Q4 2024 | 115 | 98 |
| Q1 2025 | 114 | 124 |
| Q2 2025 | 129 | 109 |
| Q3 2025 | 151 | 111 |
| Q4 2025 | 200 | 120 |
| Q1 2026 | 229 | 164 |
| Q2 2026 | 258 | 169 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2025 | $146.1m | $65.6m | 0.45 |
| Q4 2025 | $199.8m | $67.6m | 0.34 |
| Q1 2026 | $162.3m | $51.5m | 0.32 |
| Q2 2026 | $148.5m | $46.6m | 0.31 |
Biggest buyers
| BlackRock, Inc. | Added | +1.3m |
| Assenagon Asset Management S.A. | Added | +1.2m |
| STATE STREET CORP | Added | +875.2k |
| Fisher Asset Management, LLC | Added | +683.1k |
| GOLDMAN SACHS GROUP INC | Added | +670.1k |
| Balyasny Asset Management L.P. | Added | +664.5k |
| Woodline Partners LP | New | +626.8k |
| First Eagle Investment Management, LLC | Added | +561.6k |
| Boston Partners | Added | +544.2k |
| VANGUARD PORTFOLIO MANAGEMENT LLC | Added | +532.2k |
Biggest sellers
| JANE STREET GROUP, LLC | Reduced | -1.2m |
| CITADEL ADVISORS LLC | Reduced | -1.0m |
| MILLENNIUM MANAGEMENT LLC | Reduced | -871.4k |
| FMR LLC | Reduced | -699.7k |
| Encompass Capital Advisors LLC | Reduced | -651.4k |
| D. E. Shaw & Co., Inc. | Reduced | -637.6k |
| Bornite Capital Management LP | Sold out | -542.0k |
| Sourcerock Group LLC | Reduced | -421.2k |
| Westend Capital Management, LLC | Reduced | -378.1k |
| DEUTSCHE BANK AG\ | Reduced | -334.3k |
Biggest calls
| UBS Group AG | Unchanged | $52.9m1.2m shares |
| JANE STREET GROUP, LLC | Added | $20.3m441.6k shares |
| Caption Management, LLC | Added | $19.6m425.0k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $18.1m393.6k shares |
| CITADEL ADVISORS LLC | Reduced | $7.1m154.2k shares |
| Impala Asset Management LLC | New | $6.9m150.0k shares |
| IMC-Chicago, LLC | Added | $6.6m144.4k shares |
| WELLS FARGO & COMPANY/MN | New | $4.2m91.2k shares |
| SIMPLEX TRADING, LLC | Reduced | $2.9m63.4k shares |
| Point72 Asset Management, L.P. | Reduced | $2.7m59.7k shares |
Biggest puts
| JANE STREET GROUP, LLC | Added | $11.5m249.2k shares |
| CITADEL ADVISORS LLC | Added | $9.6m208.1k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $9.1m198.1k shares |
| IMC-Chicago, LLC | Added | $7.7m166.7k shares |
| Caption Management, LLC | Added | $4.1m90.0k shares |
| GROUP ONE TRADING LLC | Added | $1.4m31.2k shares |
| SIMPLEX TRADING, LLC | Reduced | $957.0k20.8k shares |
| Point72 Asset Management, L.P. | Reduced | $878.8k19.1k shares |
| HRT FINANCIAL LP | New | $874.0k19.0k shares |
| LMR Partners LLP | New | $271.5k5.9k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
GLENCORE INTERNATIONAL AG
13D · may seek influence
-6.6 pts · filed 2026-03-04
Stated purposeThe Reporting Persons remain confident in the management team and outlook of the Company, maintain a position in the Company and intend to continue to hold Common Stock for investment purposes. On March 4, 2026, the Reporting Persons monetized a portion of their investment via a sale of 6,315,245 shares in a block trade pursuant to Rule 144 and subject to customary conditions (the "Subject Sale"). The Reporting Persons may purchase or sell additional shares of Common Stock and other securities of the Issuer. Such transactions could be in the open market and/or in privately negotiated or structured transactions, provided that any such transactions would be on terms deemed favorable by the Reporting Persons. In addition, the Reporting Persons may formulate plans or proposals for, hold disc… Full filing |
30.0% |
| BlackRock, Inc. 13G · institution +1.0 pts · filed 2026-10-05 | 10.5% |
| STATE STREET CORP 13G · institution new · filed 2026-08-07 | 5.6% |
Fell to 5% or below in the last year: VANGUARD GROUP INC (0.0%, 2026-03-26)
Insider purchases and sales since 1 Apr 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q4 2024 | 0 | — | 2 | $2.0m | — |
| Q1 2025 | 0 | — | 1 | $151.2k | — |
| Q2 2025 | 0 | — | 0 | — | — |
| Q3 2025 | 0 | — | 3 | $997.2k | — |
| Q4 2025 | 0 | — | 0 | — | — |
| Q1 2026 | 0 | — | 8 | $26.2m | $15.5m |
| Q2 2026 | 0 | — | 0 | — | — |
| Q3 2026 | 0 | — | 0 | — | — |
None reported since 1 Apr 2026.
Holders, Q2 2026
| Manager | Shares | Change |
|---|---|---|
| Glencore plc 28.07% of their portfolio | 29.7m $1.4bn | Unchanged |
| BlackRock, Inc. 0.01% of their portfolio | 10.3m $474.1m | Added +1.3m |
| STATE STREET CORP 0.01% of their portfolio | 5.5m $255.0m | Added +875.2k |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.01% of their portfolio | 4.8m $219.6m | Added +532.2k |
| Assenagon Asset Management S.A. 0.09% of their portfolio | 3.1m $140.9m | Added +1.2m |
| VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 3.0m $136.8m | Added +386.4k |
| Invesco Ltd. 0.01% of their portfolio | 2.4m $111.2m | Added +341.3k |
| Sourcerock Group LLC 5.42% of their portfolio | 2.3m $104.3m | Reduced -421.2k |
| DIMENSIONAL FUND ADVISORS LP 0.02% of their portfolio | 2.2m $101.8m | Added +20.6k |
| FMR LLC 0.00% of their portfolio | 2.0m $90.2m | Reduced -699.7k |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 1.8m $85.0m | Added +306.6k |
| Fisher Asset Management, LLC 0.02% of their portfolio | 1.5m $70.6m | Added +683.1k |
| MORGAN STANLEY 0.00% of their portfolio | 1.5m $69.5m | Reduced -74.5k |
| MILLENNIUM MANAGEMENT LLC 0.03% of their portfolio | 1.1m $51.4m | Reduced -871.4k |
| GOLDMAN SACHS GROUP INC 0.01% of their portfolio | 1.0m $48.3m | Added +670.1k |
| Impala Asset Management LLC 29.42% of their portfolio | 1.0m $47.6m | Added +60.0k |
| Encompass Capital Advisors LLC 1.79% of their portfolio | 900.0k $41.4m | Reduced -651.4k |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.05% of their portfolio | 870.9k $40.1m | Added +70.7k |
| UBS Group AG 0.01% of their portfolio | 866.8k $39.9m | Added +280.1k |
| Boston Partners 0.03% of their portfolio | 854.1k $39.3m | Added +544.2k |
| Qube Research & Technologies Ltd 0.04% of their portfolio | 847.5k $39.0m | Added +257.5k |
| Allspring Global Investments Holdings, LLC 0.05% of their portfolio | 827.0k $35.6m | Added +265.0k |
| D. E. Shaw & Co., Inc. 0.02% of their portfolio | 795.7k $36.6m | Reduced -637.6k |
| Kinetic Partners Management, LP 0.85% of their portfolio | 776.7k $35.7m | Added +245.0k |
| Balyasny Asset Management L.P. 0.06% of their portfolio | 759.6k $34.9m | Added +664.5k |
| First Eagle Investment Management, LLC 0.03% of their portfolio | 724.7k $33.3m | Added +561.6k |
| Merewether Investment Management, LP 0.60% of their portfolio | 693.5k $31.9m | Added +178.7k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 682.1k $31.4m | Added +133.3k |
| Squarepoint Ops LLC 0.06% of their portfolio | 679.2k $31.3m | Added +269.1k |
| Woodline Partners LP 0.09% of their portfolio | 626.8k $28.8m | New |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 602.2k $27.7m | Reduced -6.6k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio | 594.9k $27.4m | Added +50.4k |
| WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio | 548.9k $25.3m | Added +170.5k |
| BW Gestao de Investimentos Ltda. 0.58% of their portfolio | 523.2k $24.1m | Added +214.4k |
| Mountaineer Partners Management, LLC 16.84% of their portfolio | 503.3k $23.2m | Reduced -80.7k |
| Jefferies Financial Group Inc. 0.21% of their portfolio | 486.2k $22.4m | Added +2.0k |
| Bridgewater Associates, LP 0.09% of their portfolio | 473.9k $21.8m | Reduced -258.6k |
| MASSACHUSETTS FINANCIAL SERVICES CO /MA/ 0.01% of their portfolio | 456.2k $22.3m | Added +443.7k |
| Driehaus Capital Management LLC 0.12% of their portfolio | 456.0k $21.0m | New |
| VANGUARD FIDUCIARY TRUST CO 0.00% of their portfolio | 427.3k $19.7m | Added +49.0k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 403.6k $18.6m | Added +67.8k |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.08% of their portfolio | 393.0k $18.1m | Reduced -327.7k |
| Capital World Investors 0.00% of their portfolio | 391.4k $18.0m | New |
| ROYCE & ASSOCIATES LP 0.14% of their portfolio | 372.0k $17.1m | Added +107.7k |
| CANADA PENSION PLAN INVESTMENT BOARD 0.01% of their portfolio | 365.4k $16.8m | Added +336.9k |
| Rokos Capital Management LLP 0.21% of their portfolio | 355.0k $16.3m | Reduced -81.7k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 347.2k $16.3m | Reduced -169.5k |
| Nuveen, LLC 0.00% of their portfolio | 342.0k $15.7m | Added +33.0k |
| HEALTHCARE OF ONTARIO PENSION PLAN TRUST FUND 0.02% of their portfolio | 326.5k $15.0m | Added +142.4k |
| Steamboat Capital Partners, LLC 2.92% of their portfolio | 296.7k $13.6m | Added +20.4k |
| Point72 Asset Management, L.P. 0.02% of their portfolio | 294.6k $13.6m | Reduced -274.9k |
| CITADEL ADVISORS LLC 0.01% of their portfolio | 290.0k $13.3m | Reduced -1.0m |
| PRINCIPAL FINANCIAL GROUP INC 0.01% of their portfolio | 276.8k $12.7m | Added +16.4k |
| Weiss Asset Management LP 0.14% of their portfolio | 269.9k $12.4m | Not comparable |
| BNP PARIBAS FINANCIAL MARKETS 0.01% of their portfolio | 269.2k $12.4m | Added +155.9k |
| DEUTSCHE BANK AG\ 0.00% of their portfolio | 263.7k $12.1m | Reduced -334.3k |
| CONGRESS ASSET MANAGEMENT CO 0.07% of their portfolio | 255.6k $11.8m | Added +2.2k |
| SYSTEMATIC FINANCIAL MANAGEMENT LP 0.23% of their portfolio | 252.2k $11.6m | Added +94.5k |
| CANADA LIFE ASSURANCE Co 0.02% of their portfolio | 244.3k $11.2m | Reduced -31.1k |
| BANK OF MONTREAL /CAN/ 0.00% of their portfolio | 228.6k $10.5m | Added +820 |
| Yaupon Capital Management LP 0.34% of their portfolio | 223.9k $10.3m | Added +12.7k |
| Public Sector Pension Investment Board 0.03% of their portfolio | 223.0k $10.3m | Reduced -20.9k |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 212.1k $9.8m | Added +60.2k |
| BARCLAYS PLC 0.00% of their portfolio | 209.6k $9.6m | Added +66.3k |
| FIRST TRUST ADVISORS LP 0.01% of their portfolio | 201.7k $9.3m | Added +136.1k |
| Nicholas Investment Partners, LP 0.51% of their portfolio | 198.0k $9.1m | Reduced -94.4k |
| AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 188.2k $8.7m | Added +22.0k |
| CDC Financial, Inc. 6.41% of their portfolio | 181.4k $8.3m | Reduced -65.2k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.01% of their portfolio | 179.4k $8.3m | Added +100.9k |
| VICTORY CAPITAL MANAGEMENT INC 0.00% of their portfolio | 177.1k $8.1m | Added +113.2k |
| Counterpoint Mutual Funds LLC 0.76% of their portfolio | 167.0k $7.7m | Added +155.4k |
| Drummond Knight Asset Management Pty Ltd 1.37% of their portfolio | 162.3k $7.5m | Reduced -118.8k |
| Russell Investments Group, Ltd. 0.01% of their portfolio | 157.7k $7.3m | Added +88.3k |
| RHUMBLINE ADVISERS 0.01% of their portfolio | 153.6k $7.1m | Reduced -4.6k |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 149.4k $6.9m | Added +48.7k |
| CSM Advisors, LLC 0.14% of their portfolio | 146.2k $6.7m | Reduced -9.5k |
| FRANKLIN RESOURCES INC 0.00% of their portfolio | 144.1k $6.6m | Added +19.3k |
| Insight Wealth Strategies, LLC 0.60% of their portfolio | 143.5k $6.2m | Reduced -2.6k |
| ICON ADVISERS INC/CO 1.22% of their portfolio | 140.5k $6.5m | Reduced -32.7k |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 140.3k $8.2m | Reduced -19.2k |
| Swiss National Bank 0.00% of their portfolio | 134.1k $6.2m | Added +23.6k |
| NEUBERGER BERMAN GROUP LLC 0.00% of their portfolio | 133.9k $6.2m | Added +60.8k |
| BOOTHBAY FUND MANAGEMENT, LLC 0.12% of their portfolio | 133.5k $6.1m | Added +50.5k |
| CIBC WORLD MARKET INC. 0.01% of their portfolio | 132.2k $6.1m | Reduced -28.4k |
| COHEN & STEERS, INC. 0.01% of their portfolio | 126.1k $5.8m | Added +7.9k |
| PICTON MAHONEY ASSET MANAGEMENT 0.05% of their portfolio | 125.9k $5.8m | Reduced -169.4k |
| Legal & General Group Plc 0.00% of their portfolio | 123.1k $5.7m | Added +10.5k |
| RENAISSANCE GROUP LLC 0.22% of their portfolio | 118.1k $5.4m | Added +110.7k |
| ENVESTNET ASSET MANAGEMENT INC 0.00% of their portfolio | 115.3k $5.3m | Added +32.4k |
| STATE OF WISCONSIN INVESTMENT BOARD 0.01% of their portfolio | 109.5k $5.0m | Added +9.3k |
| Cinctive Capital Management LP 0.20% of their portfolio | 107.2k $4.9m | Added +59.0k |
| BESSEMER GROUP INC 0.01% of their portfolio | 102.5k $4.7m | Unchanged |
| RAYMOND JAMES FINANCIAL INC 0.00% of their portfolio | 101.4k $4.7m | Reduced -8.2k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 100.2k $4.6m | Added +3.9k |
| Hudson Bay Capital Management LP 0.02% of their portfolio | 100.0k $4.6m | Added +92.5k |
| Y-Intercept (Hong Kong) Ltd 0.09% of their portfolio | 96.1k $4.4m | Added +5.7k |
| RENAISSANCE TECHNOLOGIES LLC 0.01% of their portfolio | 94.3k $4.3m | Reduced -45.2k |
| PRUDENTIAL FINANCIAL INC 0.00% of their portfolio | 91.1k $4.2m | Added +18.0k |
| VAN ECK ASSOCIATES CORP 0.00% of their portfolio | 89.4k $4.1m | New |
| BNP PARIBAS ASSET MANAGEMENT Holding S.A. 0.00% of their portfolio | 87.9k $4.0m | Added +75.9k |