Gulfport Energy Corporation
US ˙ NYSE ˙ US4026355028

SecurityGPOR / Gulfport Energy Corporation
InstitutionAssetmark, Inc
Latest Disclosed Ownership1,231 shares
Latest Disclosed Value $ 260,443
Assetmark, Inc reports 6.74% decrease in ownership of GPOR / Gulfport Energy Corporation

On May 6, 2026 - Assetmark, Inc filed a 13F-HR form disclosing ownership of 1,231 shares of Gulfport Energy Corporation (US:GPOR) valued at $260,443 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 23, 2026 disclosing 1,320 shares of Gulfport Energy Corporation. This represents a change in shares of -6.74% during the quarter. The current value of the position is $206,882 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)
2026-05-06 2026-03-31 13F GULFPORT ENERGY COMMON SHARES 402635502 1,231 -89 -6.74 260 -5.11 0.0005
2026-01-23 2025-12-31 13F GULFPORT ENERGY COMMON SHARES 402635502 1,320 23 1.77 275 17.09 0.0006
2025-11-06 2025-09-30 13F GULFPORT ENERGY COMMON SHARES 402635502 1,297 796 158.88 235 134.00 0.0005
2025-08-04 2025-06-30 13F GULFPORT ENERGY COMMON SHARES 402635502 501 168 50.45 101 63.93 0.0002
2025-05-06 2025-03-31 13F GULFPORT ENERGY COMMON SHARES 402635502 333 -31 -8.52 61 -8.96 0.0002
2025-02-06 2024-12-31 13F GULFPORT ENERGY COMMON SHARES 402635502 364 364 67 0.0002
2019-11-13 2019-09-30 13F GULFPORT ENERGY CORP COM COM 402635304 0 -317 -100.00 0 -100.00
2019-08-14 2019-06-30 13F GULFPORT ENERGY CORP COM COM 402635304 317 102 47.44 2 0.00 0.0000
2019-05-14 2019-03-31 13F GULFPORT ENERGY CORP COM COM 402635304 215 72 50.35 2 100.00 0.0000
2019-02-13 2018-12-31 13F GULFPORT ENERGY CORP COM COM 402635304 143 30 26.55 1 0.00 0.0000
2018-11-13 2018-09-30 13F GULFPORT ENERGY CORP COM COM 402635304 113 -6 -5.04 1 -50.00 0.0000
2018-08-01 2018-06-30 13F GULFPORT ENERGY CORP COM COM 402635304 119 0 0.00 2 100.00 0.0000
2018-05-16 2018-03-31 13F GULFPORT ENERGY CORP COM COM 402635304 119 11 10.19 1 0.00 0.0000
2018-02-13 2017-12-31 13F GULFPORT ENERGY CORP COM COM 402635304 108 108 1 0.0000
2017-11-08 2017-09-30 13F GULFPORT ENERGY CORP COM COM 402635304 0 -15 -100.00 0 0.0000
2017-08-14 2017-06-30 13F GULFPORT ENERGY CORP COM COM 402635304 15 15 0 0.0000
2017-09-14 2016-06-30 13F/A-1 GULFPORT ENERGY CORP COM COM 402635304 0 -25 -100.00 0 -100.00
2017-09-14 2016-03-31 13F/A-1 GULFPORT ENERGY CORP COM COM 402635304 25 0 0.00 1 0.00 0.0000
2016-05-13 2016-03-31 13F GULFPORT ENERGY CORP COM COM 402635304 25 0 1
2017-09-14 2015-12-31 13F/A-1 GULFPORT ENERGY CORP COM COM 402635304 25 -1 -3.85 1 0.00 0.0000
2016-02-12 2015-12-31 13F GULFPORT ENERGY CORP COM COM 402635304 25 -1 1
2016-01-05 2015-09-30 13F/A-1 GULFPORT ENERGY CORP COM COM 402635304 26 -18,208 -99.86 1 -99.86 0.0000
2015-11-10 2015-09-30 13F GULFPORT ENERGY CORP COM COM 402635304 26 1
2015-08-13 2015-06-30 13F GULFPORT ENERGY CORP COM COM 402635304 18,234 120 0.66 734 -11.78 0.0153
2015-05-12 2015-03-31 13F GULFPORT ENERGY CORP COM COM 402635304 18,114 18,114 0.00 832 0.0177
2015-02-03 2014-12-31 13F GULFPORT ENERGY CORP COM COM 402635304 0 -34,290 -100.00 0 -100.00
2014-11-10 2014-09-30 13F GULFPORT ENERGY CORP COM COM 402635304 34,290 -1,835 -5.08 1,831 -19.30 0.0423
2014-08-12 2014-06-30 13F GULFPORT ENERGY CORP COM COM 402635304 36,125 -15,560 -30.11 2,269 -38.33 0.0483
2014-05-06 2014-03-31 13F GULFPORT ENERGY CORP COM COM 402635304 51,685 -41,925 -44.79 3,679 -37.75 0.0897
2014-02-11 2013-12-31 13F GULFPORT ENERGY CORP COM COM 402635304 93,610 58,688 168.05 5,910 163.02 0.1399
2014-02-11 2013-09-30 13F/A-1 GULFPORT ENERGY CORP COM COM 402635304 34,922 34,922 2,247 0.0567
2013-11-14 2013-09-30 13F GULFPORT ENERGY CORP COM COM 402635304 34,922 2,247
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.