Kosmos Energy Ltd.
US ˙ NYSE ˙ US5006881065

SecurityKOS / Kosmos Energy Ltd.
InstitutionBanco Santander, S.A.
Latest Disclosed Ownership124,536 shares
Latest Disclosed Value $ 346,210
Banco Santander, S.A. reports 19.41% decrease in ownership of KOS / Kosmos Energy Ltd.

On May 8, 2026 - Banco Santander, S.A. filed a 13F-HR form disclosing ownership of 124,536 shares of Kosmos Energy Ltd. (US:KOS) valued at $346,210 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 154,524 shares of Kosmos Energy Ltd.. This represents a change in shares of -19.41% during the quarter. The current value of the position is $372,363 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)
2026-05-08 2026-03-31 13F KOSMOS ENERGY COM 500688106 124,536 -29,988 -19.41 346 147.14 0.0016
2026-02-13 2025-12-31 13F KOSMOS ENERGY COM 500688106 154,524 -7,396 -4.57 140 -47.76 0.0010
2025-11-12 2025-09-30 13F KOSMOS ENERGY COM 500688106 161,920 113,812 236.58 269 226.83 0.0024
2025-08-01 2025-06-30 13F KOSMOS ENERGY COM 500688106 48,108 22,588 88.51 83 41.38 0.0008
2025-05-09 2025-03-31 13F KOSMOS ENERGY COM 500688106 25,520 4,340 20.49 58 -19.44 0.0006
2025-02-07 2024-12-31 13F KOSMOS ENERGY COM 500688106 21,180 21,180 72 0.0009
2022-02-09 2021-12-31 13F KOSMOS ENERGY COM 500688106 0 -440,503 -100.00 0 -100.00
2021-11-08 2021-09-30 13F KOSMOS ENERGY COM 500688106 440,503 0 0.00 1,304 -14.44 0.0070
2021-07-29 2021-06-30 13F KOSMOS ENERGY COM 500688106 440,503 0 0.00 1,524 12.72 0.0085
2021-05-10 2021-03-31 13F KOSMOS ENERGY COM 500688106 440,503 -120,600 -21.49 1,352 2.50 0.0095
2021-02-12 2020-12-31 13F KOSMOS ENERGY COM 500688106 561,103 -2,133,109 -79.17 1,319 -49.81 0.0095
2020-11-09 2020-09-30 13F KOSMOS ENERGY COM 500688106 2,694,212 0 0.00 2,628 -41.23 0.0346
2020-08-05 2020-06-30 13F KOSMOS ENERGY COM 500688106 2,694,212 0 0.00 4,472 85.33 0.0580
2020-05-11 2020-03-31 13F KOSMOS ENERGY COM 500688106 2,694,212 0 0.00 2,413 -84.29 0.0276
2020-02-07 2019-12-31 13F KOSMOS ENERGY COM 500688106 2,694,212 31,147 1.17 15,357 -7.59 0.1418
2019-11-06 2019-09-30 13F KOSMOS ENERGY COM 500688106 2,663,065 778,208 41.29 16,618 40.62 0.1616
2019-08-07 2019-06-30 13F KOSMOS ENERGY COM 500688106 1,884,857 633,916 50.68 11,818 51.40 0.1199
2019-05-13 2019-03-31 13F KOSMOS ENERGY COM 500688106 1,250,941 1,250,941 7,806 0.0881
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.