Century Aluminum Company
US ˙ NasdaqGS ˙ US1564311082

SecurityCENX / Century Aluminum Company
InstitutionQube Research & Technologies Ltd
Latest Disclosed Ownership589,928 shares
Latest Disclosed Value $ 34,622,874
Qube Research & Technologies Ltd reports 18.76% decrease in ownership of CENX / Century Aluminum Company

On May 15, 2026 - Qube Research & Technologies Ltd filed a 13F-HR form disclosing ownership of 589,928 shares of Century Aluminum Company (US:CENX) valued at $34,622,874 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 726,192 shares of Century Aluminum Company. This represents a change in shares of -18.76% during the quarter. The current value of the position is $39,545,823 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F CENTURY ALUM COM 156431108 589,928 -136,264 -18.76 34,623 21.69 0.0385
2026-02-17 2025-12-31 13F CENTURY ALUM COM 156431108 726,192 -96,938 -11.78 28,452 17.73 0.0289
2025-11-14 2025-09-30 13F CENTURY ALUM COM 156431108 823,130 282,019 52.12 24,167 147.87 0.0250
2025-08-14 2025-06-30 13F CENTURY ALUM COM 156431108 541,111 329,298 155.47 9,751 148.03 0.0099
2025-05-15 2025-03-31 13F CENTURY ALUM COM 156431108 211,813 -211,969 -50.02 3,931 -49.09 0.0046
2025-02-14 2024-12-31 13F CENTURY ALUM COM 156431108 423,782 254,747 150.71 7,721 181.48 0.0101
2024-11-14 2024-09-30 13F CENTURY ALUM COM 156431108 169,035 169,035 2,743 0.0040
2022-08-15 2022-06-30 13F CENTURY ALUM COM 156431108 0 -9,657 -100.00 0 -100.00
2022-05-09 2022-03-31 13F CENTURY ALUM COM 156431108 9,657 9,657 254 0.0022
2021-11-12 2021-09-30 13F CENTURY ALUM COM 156431108 0 -16,382 -100.00 0 -100.00
2021-08-13 2021-06-30 13F CENTURY ALUM COM 156431108 16,382 16,382 211 0.0024
2021-02-16 2020-12-31 13F CENTURY ALUM COM 156431108 0 -87,645 -100.00 0 -100.00
2020-11-12 2020-09-30 13F CENTURY ALUM COM 156431108 87,645 87,645 624 0.0089
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.