Occidental Petroleum Corporation
CH ˙ SWX ˙ US6745991058
SecurityCH:OXY / Occidental Petroleum Corporation
InstitutionCastleark Management Llc
Latest Disclosed Ownership52,585 shares
Latest Disclosed Value $ 3,418,025
Castleark Management Llc reports 127.59% increase in ownership of OXY / Occidental Petroleum Corporation

On May 15, 2026 - Castleark Management Llc filed a 13F-HR form disclosing ownership of 52,585 shares of Occidental Petroleum Corporation (CH:OXY) valued at $3,418,025 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 23,105 shares of Occidental Petroleum Corporation. This represents a change in shares of 127.59% during the quarter.

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 OCCIDENTAL PETE COM 674599105 52,585 29,480 127.59 3,418 259.79 0.1131
2026-02-12 2025-12-31 13F OCCIDENTAL PETE COM 674599105 23,105 0 0.00 950 -12.92 0.0279
2025-11-17 2025-09-30 13F OCCIDENTAL PETE COM 674599105 23,105 0 0.00 1,092 12.47 0.0306
2025-08-18 2025-06-30 13F OCCIDENTAL PETE COM 674599105 23,105 0 0.00 971 -14.91 0.0292
2025-05-15 2025-03-31 13F OCCIDENTAL PETE COM 674599105 23,105 0 0.00 1,140 -0.09 0.0395
2025-02-18 2024-12-31 13F OCCIDENTAL PETE COM 674599105 23,105 -34,510 -59.90 1,142 -61.57 0.0398
2024-11-15 2024-09-30 13F OCCIDENTAL PETE COM 674599105 57,615 0 0.00 2,969 -18.23 0.1210
2024-08-14 2024-06-30 13F OCCIDENTAL PETE COM 674599105 57,615 0 0.00 3,631 -3.02 0.1483
2024-05-16 2024-03-31 13F OCCIDENTAL PETE COM 674599105 57,615 0 0.00 3,744 8.84 0.1558
2024-02-15 2023-12-31 13F OCCIDENTAL PETE COM 674599105 57,615 0 0.00 3,440 -7.97 0.1525
2023-11-15 2023-09-30 13F OCCIDENTAL PETE COM 674599105 57,615 33,930 143.26 3,738 168.53 0.1905
2023-08-16 2023-06-30 13F OCCIDENTAL PETE COM 674599105 23,685 0 0.00 1,393 -5.82 0.0631
2023-05-16 2023-03-31 13F OCCIDENTAL PETE COM 674599105 23,685 -3,020 -11.31 1,479 -12.13 0.0726
2023-02-10 2022-12-31 13F OCCIDENTAL PETE COM 674599105 26,705 0 0.00 1,682 2.50 0.0879
2022-11-15 2022-09-30 13F OCCIDENTAL PETE COM 674599105 26,705 -6,680 -20.01 1,641 -16.53 0.0913
2022-08-16 2022-06-30 13F OCCIDENTAL PETE COM 674599105 33,385 -11,130 -25.00 1,966 -22.17 0.1052
2022-05-16 2022-03-31 13F OCCIDENTAL PETE COM 674599105 44,515 0 0.00 2,526 95.81 0.1090
2022-02-16 2021-12-31 13F OCCIDENTAL PETE COM 674599105 44,515 -3,770 -7.81 1,290 -9.66 0.0474
2021-11-12 2021-09-30 13F OCCIDENTAL PETE COM 674599105 48,285 -33,265 -40.79 1,428 -44.00 0.0546
2021-08-17 2021-06-30 13F OCCIDENTAL PETE COM 674599105 81,550 -29,300 -26.43 2,550 -13.59 0.0857
2021-05-14 2021-03-31 13F OCCIDENTAL PETE COM 674599105 110,850 -67,880 -37.98 2,951 -4.62 0.1063
2021-02-17 2020-12-31 13F OCCIDENTAL PETE COM 674599105 178,730 178,730 3,094 0.1158
2019-08-13 2019-06-30 13F OCCIDENTAL PETE COM 674599105 0 -38,880 -100.00 0 -100.00
2019-05-14 2019-03-31 13F OCCIDENTAL PETE COM 674599105 38,880 11,370 41.33 2,574 52.40 0.0969
2019-02-12 2018-12-31 13F OCCIDENTAL PETE CORP DEL COM 674599105 27,510 -14,520 -34.55 1,689 -51.10 0.0720
2018-11-14 2018-09-30 13F OCCIDENTAL PETE CORP DEL COM 674599105 42,030 -42,050 -50.01 3,454 -50.91 0.0993
2018-08-15 2018-06-30 13F OCCIDENTAL PETE CORP DEL COM 674599105 84,080 84,080 7,036 0.2166
2017-02-15 2016-12-31 13F OCCIDENTAL PETE CORP DEL COM 674599105 0 -25,100 -100.00 0 -100.00
2016-11-15 2016-09-30 13F OCCIDENTAL PETE CORP DEL COM 674599105 25,100 0 0.00 1,830 -3.53 0.0554
2016-08-10 2016-06-30 13F OCCIDENTAL PETE CORP DEL COM 674599105 25,100 0 0.00 1,897 10.42 0.0605
2016-05-17 2016-03-31 13F OCCIDENTAL PETE CORP DEL COM 674599105 25,100 25,100 0.00 1,718 0.0537
2016-02-17 2015-12-31 13F OCCIDENTAL PETE CORP DEL COM 674599105 0 0 0 0.0000
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.