Occidental Petroleum Corporation
CH ˙ SWX ˙ US6745991058
SecurityCH:OXY / Occidental Petroleum Corporation
InstitutionRosenberg Matthew Hamilton
Latest Disclosed Ownership3,484 shares
Latest Disclosed Value $ 226,460
Rosenberg Matthew Hamilton reports 51.87% increase in ownership of OXY / Occidental Petroleum Corporation

On April 6, 2026 - Rosenberg Matthew Hamilton filed a 13F-HR form disclosing ownership of 3,484 shares of Occidental Petroleum Corporation (CH:OXY) valued at $226,460 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 5, 2026 disclosing 2,294 shares of Occidental Petroleum Corporation. This represents a change in shares of 51.87% 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)
2026-04-06 2026-03-31 13F OCCIDENTAL PETE CORP COM Stock 674599105 3,484 1,190 51.87 226 140.43 0.0464
2026-01-05 2025-12-31 13F OCCIDENTAL PETE CORP COM Stock 674599105 2,294 -149 -6.10 94 -18.26 0.0195
2025-11-10 2025-09-30 13F OCCIDENTAL PETE CORP COM Stock 674599105 2,443 0 0.00 115 12.75 0.0250
2025-07-28 2025-06-30 13F OCCIDENTAL PETE CORP COM Stock 674599105 2,443 -791 -24.46 103 -35.85 0.0239
2025-04-28 2025-03-31 13F OCCIDENTAL PETE CORP COM Stock 674599105 3,234 -2,026 -38.52 160 -38.61 0.0400
2025-01-14 2024-12-31 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,260 -139 -2.57 260 -6.83 0.0675
2024-10-28 2024-09-30 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,399 -58 -1.06 278 -18.95 0.0728
2024-07-26 2024-06-30 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,457 -82 -1.48 343 -6.54 0.1014
2024-04-22 2024-03-31 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,539 119 2.20 368 13.62 0.1062
2024-01-16 2023-12-31 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,420 65 1.21 324 -6.92 0.0996
2023-10-11 2023-09-30 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,355 140 2.68 347 13.40 0.1157
2023-07-26 2023-06-30 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,215 6 0.12 307 -5.85 0.1037
2023-04-17 2023-03-31 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,209 0 0.00 325 -0.91 0.1049
2023-01-19 2022-12-31 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,209 0 0.00 328 2.50 0.1112
2022-10-21 2022-09-30 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,209 171 3.39 320 4.92 0.1237
2022-07-15 2022-06-30 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,038 0 0.00 305 6.64 0.1150
2022-04-14 2022-03-31 13F OCCIDENTAL PETE CORP COM Stock 674599105 5,038 335 7.12 286 110.29 0.1000
2022-01-20 2021-12-31 13F OCCIDENTAL PETE COM 674599105 4,703 2,322 97.52 136 94.29 0.0484
2021-10-12 2021-09-30 13F OCCIDENTAL PETE COM 674599105 2,381 0 0.00 70 -5.41 0.0277
2021-07-26 2021-06-30 13F OCCIDENTAL PETE COM 674599105 2,381 -138 -5.48 74 10.45 0.0385
2021-04-30 2021-03-31 13F OCCIDENTAL PETE COM 674599105 2,519 1,344 114.38 67 235.00 0.0382
2021-02-03 2020-12-31 13F OCCIDENTAL PETE COM 674599105 1,175 0 0.00 20 66.67 0.0125
2020-10-16 2020-09-30 13F OCCIDENTAL PETE COM 674599105 1,175 0 0.00 12 -45.45 0.0088
2020-08-04 2020-06-30 13F OCCIDENTAL PETE COM 674599105 1,175 1,175 22 0.0175
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.