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 ($3.8m this quarter). Holder counts are more reliable. Shares outstanding: 93.3m as of 2025-08-05, 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 ≈ $18.02. Options: 17 managers hold calls ($67.2m notional), 14 hold puts ($37.5m).
Trends to Q2 2025
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 |
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 2023 | 81 | 81 |
| Q4 2023 | 87 | 82 |
| Q1 2024 | 79 | 99 |
| Q2 2024 | 99 | 93 |
| Q3 2024 | 101 | 106 |
| Q4 2024 | 115 | 98 |
| Q1 2025 | 114 | 124 |
| Q2 2025 | 129 | 109 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2024 | $40.4m | $14.9m | 0.37 |
| Q4 2024 | $66.2m | $21.9m | 0.33 |
| Q1 2025 | $55.1m | $20.2m | 0.37 |
| Q2 2025 | $67.2m | $37.5m | 0.56 |
Biggest buyers
| Boston Partners | Added | +1.3m |
| Sourcerock Group LLC | Added | +1.2m |
| ROYAL BANK OF CANADA | Added | +556.3k |
| MARSHALL WACE, LLP | New | +521.6k |
| MILLENNIUM MANAGEMENT LLC | Added | +478.7k |
| STATE STREET CORP | Added | +426.3k |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC | Added | +408.1k |
| BANK OF AMERICA CORP /DE/ | Added | +372.9k |
| Qube Research & Technologies Ltd | Added | +329.3k |
| ICON ADVISERS INC/CO | New | +325.2k |
Biggest sellers
| Pertento Partners LLP | Sold out | -733.9k |
| Nuveen, LLC | Reduced | -674.6k |
| Encompass Capital Advisors LLC | Reduced | -645.5k |
| Penn Capital Management Company, LLC | Sold out | -518.4k |
| Invesco Ltd. | Reduced | -398.4k |
| NEW YORK STATE COMMON RETIREMENT FUND | Reduced | -344.5k |
| Park West Asset Management LLC | Sold out | -309.3k |
| MORGAN STANLEY | Reduced | -287.1k |
| Alberta Investment Management Corp | Sold out | -265.0k |
| Fisher Asset Management, LLC | Reduced | -260.0k |
Biggest calls
| UBS Group AG | Unchanged | $20.7m1.2m shares |
| PEAK6 LLC | Added | $11.5m640.4k shares |
| MOORE CAPITAL MANAGEMENT, LP | New | $8.7m483.8k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $8.3m458.3k shares |
| BANK OF AMERICA CORP /DE/ | Added | $4.7m260.7k shares |
| JANE STREET GROUP, LLC | Reduced | $2.6m145.2k shares |
| CITADEL ADVISORS LLC | Reduced | $2.3m129.3k shares |
| GROUP ONE TRADING LLC | Added | $1.9m106.9k shares |
| IMC-Chicago, LLC | Added | $1.7m93.4k shares |
| SIMPLEX TRADING, LLC | Reduced | $1.4m79.6k shares |
Biggest puts
| TWO SIGMA INVESTMENTS, LP | Unchanged | $9.8m542.2k shares |
| BANK OF AMERICA CORP /DE/ | New | $8.3m460.2k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $4.5m247.9k shares |
| PEAK6 LLC | New | $4.0m223.4k shares |
| CITADEL ADVISORS LLC | Reduced | $2.8m156.0k shares |
| JANE STREET GROUP, LLC | Reduced | $2.2m122.7k shares |
| Caption Management, LLC | New | $1.8m99.1k shares |
| SIMPLEX TRADING, LLC | Added | $1.5m81.0k shares |
| GROUP ONE TRADING LLC | Added | $1.0m55.8k shares |
| IMC-Chicago, LLC | Added | $679.4k37.7k 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 in Q2 2025
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 |
|---|---|---|---|---|---|
| Q3 2023 | 0 | — | 0 | — | — |
| Q4 2023 | 0 | — | 3 | $2.1m | — |
| Q1 2024 | 0 | — | 1 | $40.0k | — |
| Q2 2024 | 0 | — | 1 | $972.6k | — |
| Q3 2024 | 0 | — | 0 | — | — |
| Q4 2024 | 0 | — | 2 | $2.0m | — |
| Q1 2025 | 0 | — | 1 | $151.2k | — |
| Q2 2025 | 0 | — | 0 | — | — |
None reported in Q2 2025.
Holders, Q2 2025
| Manager | Shares | Change |
|---|---|---|
| Glencore plc 85.65% of their portfolio | 40.1m $721.8m | Added +16.5k |
| BlackRock, Inc. 0.00% of their portfolio | 10.2m $183.1m | Added +266.6k |
| VANGUARD GROUP INC 0.00% of their portfolio | 5.8m $104.0m | Added +55.5k |
| STATE STREET CORP 0.00% of their portfolio | 3.7m $66.1m | Added +426.3k |
| DIMENSIONAL FUND ADVISORS LP 0.01% of their portfolio | 3.1m $55.4m | Added +234.1k |
| CITADEL ADVISORS LLC 0.03% of their portfolio | 1.9m $34.6m | Reduced -64.0k |
| Boston Partners 0.03% of their portfolio | 1.7m $31.2m | Added +1.3m |
| WEXFORD CAPITAL LP 7.43% of their portfolio | 1.5m $26.6m | Added +308.3k |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.05% of their portfolio | 1.4m $25.8m | Reduced -33.6k |
| Sourcerock Group LLC 1.34% of their portfolio | 1.4m $25.7m | Added +1.2m |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 1.3m $23.4m | Added +6.4k |
| Woodline Partners LP 0.12% of their portfolio | 1.3m $23.2m | Added +248.7k |
| Fisher Asset Management, LLC 0.01% of their portfolio | 1.1m $19.2m | Reduced -260.0k |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 1.0m $18.1m | Added +372.9k |
| WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio | 981.6k $17.7m | Added +287.9k |
| MORGAN STANLEY 0.00% of their portfolio | 848.0k $15.3m | Reduced -287.1k |
| Impala Asset Management LLC 9.36% of their portfolio | 803.9k $14.5m | Reduced -128.3k |
| Mountaineer Partners Management, LLC 8.40% of their portfolio | 705.1k $12.7m | Added +65.8k |
| ROYAL BANK OF CANADA 0.00% of their portfolio | 568.0k $10.2m | Added +556.3k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio | 551.6k $9.9m | Added +13.9k |
| UBS Group AG 0.00% of their portfolio | 543.5k $9.8m | Added +89.4k |
| VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.04% of their portfolio | 541.6k $9.8m | Added +408.1k |
| Qube Research & Technologies Ltd 0.01% of their portfolio | 541.1k $9.8m | Added +329.3k |
| Invesco Ltd. 0.00% of their portfolio | 537.5k $9.7m | Reduced -398.4k |
| MARSHALL WACE, LLP 0.01% of their portfolio | 521.6k $9.4m | New |
| MILLENNIUM MANAGEMENT LLC 0.01% of their portfolio | 512.5k $9.2m | Added +478.7k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 508.4k $9.2m | Reduced -18.3k |
| South Dakota Investment Council 0.15% of their portfolio | 438.4k $7.9m | Added +159.7k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 384.0k $6.9m | Added +260.0k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 343.6k $6.2m | Added +542 |
| First Eagle Investment Management, LLC 0.01% of their portfolio | 338.1k $6.1m | Reduced -27.0k |
| ICON ADVISERS INC/CO 1.34% of their portfolio | 325.2k $5.9m | New |
| ADAGE CAPITAL PARTNERS GP, L.L.C. 0.01% of their portfolio | 290.0k $5.2m | Added +35.0k |
| Verition Fund Management LLC 0.03% of their portfolio | 284.4k $5.1m | Added +250.1k |
| D. E. Shaw & Co., Inc. 0.00% of their portfolio | 268.7k $4.8m | Added +240.3k |
| CSM Advisors, LLC 0.14% of their portfolio | 262.0k $4.7m | New |
| PRINCIPAL FINANCIAL GROUP INC 0.00% of their portfolio | 259.2k $4.7m | Reduced -67.6k |
| Squarepoint Ops LLC 0.01% of their portfolio | 252.3k $4.5m | Added +147.1k |
| Russell Investments Group, Ltd. 0.01% of their portfolio | 250.3k $4.5m | Added +121.0k |
| Balyasny Asset Management L.P. 0.01% of their portfolio | 247.1k $4.5m | Added +68.2k |
| Bastion Asset Management Inc. 1.99% of their portfolio | 239.5k $4.3m | Added +78.0k |
| Monaco Asset Management SAM 1.57% of their portfolio | 230.0k $4.1m | Added +92.5k |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 224.7k $4.0m | Reduced -154.6k |
| Thomist Capital Management, LP 2.41% of their portfolio | 221.7k $4.0m | Added +184.1k |
| CONGRESS ASSET MANAGEMENT CO 0.03% of their portfolio | 216.9k $3.9m | Reduced -19 |
| CoreCommodity Management, LLC 0.60% of their portfolio | 203.9k $3.7m | Added +65.3k |
| STATE OF WISCONSIN INVESTMENT BOARD 0.01% of their portfolio | 203.6k $3.7m | Added +51.8k |
| Assenagon Asset Management S.A. 0.01% of their portfolio | 200.9k $3.6m | Reduced -96.9k |
| COHEN & STEERS, INC. 0.01% of their portfolio | 196.0k $3.5m | Reduced -6.4k |
| Hartree Partners, LP 1.00% of their portfolio | 195.2k $3.5m | New |
| Steamboat Capital Partners, LLC 0.98% of their portfolio | 191.4k $3.4m | Reduced -3.6k |
| JACOBS LEVY EQUITY MANAGEMENT, INC 0.01% of their portfolio | 190.7k $3.4m | Reduced -8.6k |
| Soviero Asset Management, LP 2.51% of their portfolio | 190.0k $3.4m | New |
| Public Sector Pension Investment Board 0.01% of their portfolio | 178.1k $3.2m | Added +13.3k |
| AMERICAN CENTURY COMPANIES INC 0.00% of their portfolio | 155.9k $2.8m | Added +18.8k |
| RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio | 155.6k $2.8m | New |
| JANE STREET GROUP, LLC 0.00% of their portfolio | 154.6k $2.8m | Reduced -40.6k |
| ANTIPODES PARTNERS Ltd 0.09% of their portfolio | 153.1k $2.8m | New |
| RHUMBLINE ADVISERS 0.00% of their portfolio | 147.1k $2.7m | Added +4.7k |
| JPMORGAN CHASE & CO 0.00% of their portfolio | 147.0k $2.6m | Added +9.7k |
| SummitTX Capital, L.P. 0.11% of their portfolio | 143.1k $2.6m | Reduced -54.9k |
| Legal & General Group Plc 0.00% of their portfolio | 132.4k $2.4m | Added +4.3k |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 130.2k $2.3m | Reduced -11.0k |
| RAYMOND JAMES FINANCIAL INC 0.00% of their portfolio | 123.4k $2.2m | Added +20.8k |
| Nuveen, LLC 0.00% of their portfolio | 118.8k $2.1m | Reduced -674.6k |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 115.2k $2.1m | Added +4.8k |
| BNP PARIBAS FINANCIAL MARKETS 0.00% of their portfolio | 114.0k $2.1m | Added +17.0k |
| Swiss National Bank 0.00% of their portfolio | 105.8k $1.9m | Reduced -2.2k |
| BARCLAYS PLC 0.00% of their portfolio | 104.8k $1.9m | Added +10.3k |
| Encompass Capital Advisors LLC 0.08% of their portfolio | 104.5k $1.9m | Reduced -645.5k |
| LMR Partners LLP 0.03% of their portfolio | 104.0k $1.9m | Reduced -28.0k |
| DEUTSCHE BANK AG\ 0.00% of their portfolio | 100.4k $1.8m | Reduced -6.6k |
| INTECH INVESTMENT MANAGEMENT LLC 0.02% of their portfolio | 99.2k $1.8m | Reduced -35.9k |
| PRUDENTIAL FINANCIAL INC 0.00% of their portfolio | 98.2k $1.8m | Reduced -48.2k |
| VICTORY CAPITAL MANAGEMENT INC 0.00% of their portfolio | 97.9k $1.8m | Added +36.2k |
| Brevan Howard Capital Management LP 0.02% of their portfolio | 85.3k $1.5m | Added +66.7k |
| WINTON GROUP Ltd 0.08% of their portfolio | 84.5k $1.5m | Reduced -1.0k |
| TWO SIGMA INVESTMENTS, LP 0.00% of their portfolio | 81.8k $1.5m | Reduced -110.7k |
| NEW YORK STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 81.7k $1.5m | Reduced -12.4k |
| State of Wyoming 0.17% of their portfolio | 77.5k $1.4m | New |
| Lighthouse Investment Partners, LLC 0.06% of their portfolio | 73.6k $1.3m | Added +3.6k |
| BOOTHBAY FUND MANAGEMENT, LLC 0.04% of their portfolio | 71.9k $1.3m | Added +61.2k |
| ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio | 70.7k $1.3m | Added +10.5k |
| Jump Financial, LLC 0.01% of their portfolio | 64.9k $1.2m | New |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.00% of their portfolio | 63.7k $1.1m | Reduced -11.2k |
| Aldebaran Capital, LLC 1.09% of their portfolio | 61.2k $1.1m | Reduced -110 |
| Lombard Odier Asset Management (USA) Corp 0.27% of their portfolio | 60.4k $1.1m | Reduced -2.7k |
| AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 54.7k $985.1k | Added +15.7k |
| ALGERT GLOBAL LLC 0.02% of their portfolio | 53.5k $963.9k | Reduced -136.8k |
| HSBC HOLDINGS PLC 0.00% of their portfolio | 52.4k $946.9k | Added +27.0k |
| Dynamic Technology Lab Private Ltd 0.12% of their portfolio | 48.6k $876.0k | New |
| CANADA LIFE ASSURANCE Co 0.00% of their portfolio | 48.2k $869.0k | Added +3.6k |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 48.0k $864.5k | Reduced -3.8k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio | 46.5k $839.0k | Added +1.9k |
| CITIGROUP INC 0.00% of their portfolio | 46.0k $829.5k | Reduced -38.2k |
| JENNISON ASSOCIATES LLC 0.00% of their portfolio | 45.2k $814.0k | Reduced -1.9k |
| FRANKLIN RESOURCES INC 0.00% of their portfolio | 44.9k $809.5k | Reduced -793 |
| Centiva Capital, LP 0.05% of their portfolio | 44.7k $804.7k | Added +8.1k |
| Quantbot Technologies LP 0.02% of their portfolio | 41.4k $745.7k | Reduced -79.5k |
| BANK OF MONTREAL /CAN/ 0.00% of their portfolio | 40.2k $723.7k | Reduced -131.9k |