Diamondback Energy, Inc.
US ˙ NasdaqGS ˙ US25278X1090

SecurityFANG / Diamondback Energy, Inc.
InstitutionRhumbline Advisers
Latest Disclosed Ownership358,418 shares
Latest Disclosed Value $ 70,891,386
Rhumbline Advisers reports 0.89% decrease in ownership of FANG / Diamondback Energy, Inc.

On May 12, 2026 - Rhumbline Advisers filed a 13F-HR form disclosing ownership of 358,418 shares of Diamondback Energy, Inc. (US:FANG) valued at $70,891,496 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 361,638 shares of Diamondback Energy, Inc.. This represents a change in shares of -0.89% during the quarter. The current value of the position is $69,038,475 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)
2026-05-12 2026-03-31 13F DIAMONDBACK ENERGY COM 25278X109 358,418 -3,220 -0.89 70,891 30.40 0.0606
2026-02-13 2025-12-31 13F DIAMONDBACK ENERGY COM 25278X109 361,638 -7,370 -2.00 54,365 2.95 0.0440
2025-11-06 2025-09-30 13F DIAMONDBACK ENERGY COM 25278X109 369,008 15,401 4.36 52,805 8.68 0.0424
2025-08-12 2025-06-30 13F DIAMONDBACK ENERGY COM 25278X109 353,607 -158 -0.04 48,586 -14.10 0.0416
2025-05-29 2025-03-31 13F/A-1 DIAMONDBACK ENERGY COM 25278X109 353,765 12,534 3.67 56,560 1.17 0.0529
2025-04-08 2025-03-31 13F DIAMONDBACK ENERGY COM 25278X109 353,765 12,534 56,560 0.0529
2025-05-29 2024-12-31 13F/A-1 DIAMONDBACK ENERGY COM 25278X109 341,231 5,882 1.75 55,904 -3.31 0.0500
2025-01-30 2024-12-31 13F DIAMONDBACK ENERGY COM 25278X109 341,231 5,882 55,904 0.0500
2024-11-12 2024-09-30 13F DIAMONDBACK ENERGY COM 25278X109 335,349 -7,320 -2.14 57,814 -15.72 0.0522
2024-08-01 2024-06-30 13F DIAMONDBACK ENERGY COM 25278X109 342,669 4,749 1.41 68,599 2.44 0.0645
2024-05-09 2024-03-31 13F DIAMONDBACK ENERGY COM 25278X109 337,920 -38,945 -10.33 66,966 14.58 0.0643
2024-02-08 2023-12-31 13F DIAMONDBACK ENERGY COM 25278X109 376,865 -3,827 -1.01 58,444 -0.88 0.0613
2023-11-09 2023-09-30 13F DIAMONDBACK ENERGY COM 25278X109 380,692 31,308 8.96 58,961 28.47 0.0684
2023-08-08 2023-06-30 13F DIAMONDBACK ENERGY COM 25278X109 349,384 -12,781 -3.53 45,895 95,514.58 0.0514
2023-05-11 2023-03-31 13F DIAMONDBACK ENERGY COM 25278X109 362,165 19,159 5.59 49 -99.90 0.0604
2023-02-14 2022-12-31 13F DIAMONDBACK ENERGY COM 25278X109 343,006 26,126 8.24 46,916 22.91 0.0631
2022-11-10 2022-09-30 13F DIAMONDBACK ENERGY COM 25278X109 316,880 16,334 5.43 38,171 4.83 0.0569
2022-08-11 2022-06-30 13F DIAMONDBACK ENERGY COM 25278X109 300,546 13,195 4.59 36,411 -7.56 0.0531
2022-05-12 2022-03-31 13F DIAMONDBACK ENERGY COM 25278X109 287,351 -14,699 -4.87 39,390 20.92 0.0507
2022-02-10 2021-12-31 13F DIAMONDBACK ENERGY COM 25278X109 302,050 -3,307 -1.08 32,576 12.69 0.0399
2021-11-12 2021-09-30 13F DIAMONDBACK ENERGY COM 25278X109 305,357 -12,034 -3.79 28,908 -2.99 0.0391
2021-08-05 2021-06-30 13F DIAMONDBACK ENERGY COM 25278X109 317,391 -15,532 -4.67 29,800 21.80 0.0391
2021-05-06 2021-03-31 13F DIAMONDBACK ENERGY COM 25278X109 332,923 44,421 15.40 24,467 75.23 0.0332
2021-02-10 2020-12-31 13F DIAMONDBACK ENERGY COM 25278X109 288,502 -12 -0.00 13,963 60.68 0.0193
2020-11-12 2020-09-30 13F DIAMONDBACK ENERGY COM 25278X109 288,514 2,395 0.84 8,690 -27.37 0.0136
2020-08-13 2020-06-30 13F DIAMONDBACK ENERGY COM 25278X109 286,119 8,947 3.23 11,965 64.76 0.0200
2020-05-06 2020-03-31 13F DIAMONDBACK ENERGY COM 25278X109 277,172 15,102 5.76 7,262 -70.16 0.0152
2020-02-05 2019-12-31 13F DIAMONDBACK ENERGY COM 25278X109 262,070 12,053 4.82 24,336 8.26 0.0407
2019-10-23 2019-09-30 13F DIAMONDBACK ENERGY COM 25278X109 250,017 6,738 2.77 22,479 -15.21 0.0411
2019-08-14 2019-06-30 13F DIAMONDBACK ENERGY COM 25278X109 243,279 4,710 1.97 26,510 9.45 0.0498
2019-05-01 2019-03-31 13F DIAMONDBACK ENERGY COM 25278X109 238,569 -23,779 -9.06 24,222 -0.40 0.0469
2019-01-31 2018-12-31 13F DIAMONDBACK ENERGY COM 25278X109 262,348 170,136 184.51 24,320 95.09 0.0529
2018-11-07 2018-09-30 13F DIAMONDBACK ENERGY COM 25278X109 92,212 -1,954 -2.08 12,466 0.62 0.0241
2018-08-06 2018-06-30 13F DIAMONDBACK ENERGY COM 25278X109 94,166 -8,891 -8.63 12,389 -4.99 0.0250
2018-05-02 2018-03-31 13F DIAMONDBACK ENERGY COM 25278X109 103,057 1,052 1.03 13,039 1.25 0.0272
2018-02-09 2017-12-31 13F DIAMONDBACK ENERGY COM 25278X109 102,005 -892 -0.87 12,878 27.76 0.0262
2017-11-06 2017-09-30 13F DIAMONDBACK ENERGY COM 25278X109 102,897 1,702 1.68 10,080 12.16 0.0219
2017-08-02 2017-06-30 13F DIAMONDBACK ENERGY COM 25278X109 101,195 1,194 1.19 8,987 -13.35 0.0205
2017-05-02 2017-03-31 13F DIAMONDBACK ENERGY COM 25278X109 100,001 19,481 24.19 10,372 27.47 0.0242
2017-01-27 2016-12-31 13F DIAMONDBACK ENERGY COM 25278X109 80,520 8,158 11.27 8,137 16.48 0.0206
2016-11-08 2016-09-30 13F DIAMONDBACK ENERGY COM 25278X109 72,362 8,596 13.48 6,986 20.12 0.0193
2016-08-11 2016-06-30 13F DIAMONDBACK ENERGY COM 25278X109 63,766 12,527 24.45 5,816 47.05 0.0172
2016-05-02 2016-03-31 13F Diamondback Energy COM 25278X109 51,239 4,225 8.99 3,955 25.76 0.0123
2016-02-03 2015-12-31 13F Diamondback Energy COM 25278X109 47,014 5,730 13.88 3,145 17.92 0.0101
2015-11-04 2015-09-30 13F Diamondback Energy COM 25278X109 41,284 3,460 9.15 2,667 -6.45 0.0091
2015-08-04 2015-06-30 13F Diamondback Energy COM 25278X109 37,824 -5,049 -11.78 2,851 -13.45 0.0091
2015-05-12 2015-03-31 13F Diamondback Energy COM 25278X109 42,873 8,095 23.28 3,294 58.44 0.0095
2015-02-06 2014-12-31 13F Diamondback Energy COM 25278X109 34,778 -1,825 -4.99 2,079 -24.04 0.0060
2014-11-12 2014-09-30 13F Diamondback Energy COM 25278X109 36,603 2,625 7.73 2,737 -9.28 0.0082
2014-08-06 2014-06-30 13F Diamondback Energy COM 25278X109 33,978 15,274 81.66 3,017 139.63 0.0089
2014-05-06 2014-03-31 13F Diamondback Energy COM 25278X109 18,704 -320 -1.68 1,259 25.15 0.0037
2014-02-03 2013-12-31 13F Diamondback Energy COM 25278X109 19,024 2,120 12.54 1,006 39.53 0.0030
2013-11-05 2013-09-30 13F Diamondback Energy COM 25278X109 16,904 1,239 7.91 721 38.12 0.0022
2013-08-07 2013-06-30 13F Diamondback Energy COM 25278X109 15,665 15,665 522 0.0017
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.