PRIMEENERGY RESOURCES CORP

Our executive offices, as well as offices of Prime Operating Company and EOWS Midland Company are located in leased premises in Houston, Texas.

We maintain district offices in Midland, Texas, and Oklahoma City, Oklahoma and have field offices in Midland, Texas, as well as, Garvin, Oklahoma.

Substantially all of our oil and gas properties are subject to a mortgage given to collateralize indebtedness or are subject to being mortgaged upon request by our lenders for additional collateral.

The information set forth below concerning our properties, activities, and oil and gas reserves includes our interests in affiliated entities.

The following table sets forth the exploratory and development drilling experience with respect to wells in which we participated during the three years ended December 31, 2025.

Oil and Gas Production

As of December 31, 2025, we had ownership interest in the following number of gross and net producing oil and gas wells(1).

The following table shows our net production of oil, NGL and natural gas for each of the three years ended December 31, 2025. “Net” production is net after royalty interests of others are deducted and is determined by multiplying the gross production volume of properties in which we have an interest by the percentage of the leasehold, mineral or royalty interest owned by us.

The following table sets forth our average sales prices together with our average production costs per unit of production for the three years ended December 31, 2025.

Acreage

The following table sets forth the approximate gross and net undeveloped acreage in which we have leasehold and mineral interests as of December 31, 2025. “Undeveloped acreage” is acreage on which wells have not been drilled or completed to a point that would permit the production of commercial quantities of oil and gas, regardless of whether or not such acreage contains proved reserves.

Total Net Undeveloped Acreage Expiration

In the event that production is not established, or we take no action to extend or renew the terms of our leases, our net undeveloped acreage that will expire over the next three years, as of December 31, 2025, is zero acres for the year ending December 31, 2026, zero acres in 2027, and zero acres in 2028.

Reserves

All of our interests in proved developed and undeveloped oil and gas properties have been evaluated by Ryder Scott Company, L.P. for each of the three years ended December 31, 2025. The professional qualifications of the technical persons primarily responsible for overseeing the preparation of the reserve estimates can be found in Exhibit 99.1, the Ryder Scott Company, L.P. Report on Registrant’s Reserves Estimates. In matters related to the preparation of our reserve estimates, our district managers report to the Engineering Data manager, who maintains oversight and compliance responsibility for the internal reserve estimate process and provides oversight for the annual preparation of reserve estimates of 100% of our year-end reserves by our independent third-party engineers, Ryder Scott Company, L.P. The members of our districts consist of degreed engineers with over twenty-five years of industry experience and between ten and twenty-five years of experience managing our reserves. Our Engineering manager, the technical person primarily responsible for overseeing the preparation of reserves estimates, holds a Bachelor degree in Petroleum Engineering and has over thirty years of experience in the oil and gas industry.

See Part II, Item 8 “Financial Statements and Supplementary Data”, for additional discussions regarding proved reserves and their related cash flows. All of our reserves are located within the continental United States. The following table summarizes our oil and gas reserves at each of the respective dates:

In 2023, the Company partnered with four operators in the drilling of 57 horizontal wells: 54 of these located in West Texas and three located in Oklahoma. At year-end 2023, 23 of these wells had been completed and the remaining 34 were completed in 2024. In those wells completed in 2023 the Company invested approximately $42.8 million and in the 34 remaining West Texas wells completed in 2024, the total investment, including central facilities, was approximately $81.3 million. At year-end 2023, six of the 34 wells completed in 2024 were categorized as probable undeveloped, therefore, their non-proved reserves were not included in the reserve report that reported only proved reserves. At year-end 2023, the Company had 15,489 MBOE of proved undeveloped reserves attributable to 52 undeveloped wells, 42 of which were in the process of being drilled or completed at year-end.

In 2024, the Company invested $113 million in drilling and completion of 48 new horizontals in West Texas: 47 of these are located in Reagan County, and one is located in Upton County. In Reagan County, the Company joined Double Eagle in 33 new horizontals with an average 28.2% interest and invested approximately $66 million. Also in Reagan County, we participated with Civitas in 14 horizontals on the “Christi” tract, carrying an average of 39% interest and investing roughly $46.7 million. Also in 2024, in Upton County, we participated with Pioneer Natural Resources in one 2-mile-long horizontal with 3.94% interest, investing approximately $425,700.

At year-end 2024, the Company participated in 21 horizontals in West Texas. Of these 21 wells, six are located in Upton County, operated by Apache Corporation; three of the six were completed by year-end and three were completed after the first of the year and all were brought online in May, 2025. The remaining 15 of the 21 wells, located on our “OG” tracts and operated by Double Eagle, were on production by September 2025. At year-end 2024, the Company had 6,224 MBOE of proved undeveloped reserves attributable to 33 undeveloped wells.

In early March 2025, Ovintiv Mid-Continent spud two “Jennifer 1407” wells in Canadian County, Oklahoma; we participated for approximately 3.14% interest and invested $405,000, these wells were completed in May 2025. In the second and third quarters of 2025, we participated in fifteen new horizontals in the Midland Basin of West Texas: these 15 wells are operated by Double Eagle on our “Full House” tract in Reagan County in which the Company participated with approximately 27% interest and invested approximately $30.1 million. In addition to the Reagan County activity, the company participated in eight “Horseshoe” wells in Midland County with Vital Energy. Drilling activity with these wells began in the second quarter and the wells were put on production during the fourth quarter of 2025. The company has an average of 8.2% interest in these eight wells and invested approximately $5.4 million. We also participated with Devon Energy Production on two "Evelyn" wells in Kingfisher County, Oklahoma; we participated with approximately 9.95% interest and $1.4 million. These wells were drilled in July 2025 and completed November 2025. In total in these 27 wells, we invested approximately $37.3 million.

At year-end 2025, the Company participated in 27 horizontals in West Texas and Oklahoma. Of these 27 wells, twenty three of the wells are located in West Texas and the remaining four in Oklahoma. The West Texas wells consisted of eight wells located in Midland County and 15 wells located in Reagan County. The four wells in Oklahoma were located in Canadian and Kingfisher Counties with each county having two wells. At year-end 2025, the Company had 5,011 MBOE of proved undeveloped reserves attributable to 37 undeveloped wells.

The estimated future net revenue (using current prices and costs as of those dates) and the present value of future net revenue (at a 10% discount for estimated timing of cash flow) for our proved developed and proved undeveloped oil and gas reserves at the end of each of the three years ended December 31, 2025, are summarized as follows (in thousands of dollars):

The PV10 Value represents the discounted future net cash flows attributable to our proved oil and gas reserves before income tax, discounted at 10%. Although this measure is not in accordance with U.S. generally accepted accounting principles (“GAAP”), we believe that the presentation of the PV10 Value is relevant and useful to investors because it presents the discounted future net cash flow attributable to proved reserves prior to taking into account corporate future income taxes and the current tax structure. We use this measure when assessing the potential return on investment related to oil and gas properties. The PV10 of future income taxes represents the sole reconciling item between this non-GAAP PV10 Value versus the GAAP measure presented in the standardized measure of discounted cash flow. A reconciliation of these values is presented in the last three columns of the table above. The standardized measure of discounted future net cash flows represents the present value of future cash flows attributable to proved oil and natural gas reserves after income tax, discounted at 10%.

“Proved developed” oil and gas reserves are reserves that can be expected to be recovered from existing wells with existing equipment and operating methods. “Proved undeveloped” oil and gas reserves are reserves that are expected to be recovered from new wells on undrilled acreage, or from existing wells where a relatively major expenditure is required for recompletion.

In accordance with U.S. generally accepted accounting principles, product prices are determined using the twelve-month average oil and gas index prices, calculated as the unweighted arithmetic average for the first day of the month price for each month, adjusted for oilfield or gas gathering hub and wellhead price differentials (e.g. grade, transportation, gravity, sulfur, and basic sediment and water) as appropriate. Also, in accordance with SEC specifications and U.S. generally accepted accounting principles, changes in market prices subsequent to December 31 are not considered.

While it may be reasonably anticipated that the prices received for the sale of our production may be higher or lower than the prices used in this evaluation, as described above, and the operating costs relating to such production may also increase or decrease from existing levels, such possible changes in prices and costs were, in accordance with rules adopted by the SEC, omitted from consideration in making this evaluation for the SEC case. Actual volumes produced, prices received and costs incurred may vary significantly from the SEC case.

Natural gas prices, based on the twelve-month average of the first-of-the-month Henry Hub index price, were $3.39 per MMBtu in 2025 as compared to $2.13 per MMBtu in 2024 and $2.64 per MMBtu in 2023. Oil prices, based on the West Texas Intermediate (WTI) Light Sweet Crude first-of-the-month average spot price, were $65.34 per barrel in 2025 as compared to $75.48 per barrel in 2024, and $78.22 per barrel in 2023. Since January 1, 2024, we have not filed any estimates of our oil and gas reserves with, nor were any such estimates included in any reports to, any federal authority or agency, other than the Securities and Exchange Commission.

District Information

The following table represents certain reserves and well information as of December 31, 2025.

In West Texas, we have a field service group to service our operated wells and locations as well as third-party operators in the area. These services consist of well service support, site preparation and construction services for drilling and workover operations. Our operations are performed utilizing workover or swab rigs, saltwater disposal facilities, and trucks we own that are operated by our field employees.

Gulf Coast Region

Our production and development activities in the Gulf Coast region are concentrated in southeast and east Texas. This region is managed from our office in Houston, Texas. Principal producing intervals are in the Wilcox, Hackberry, and Yegua formations at depths ranging from 6,000 to 12,000 feet. We had 96 producing wells (19 net) in the Gulf Coast region as of December 31, 2025, of which 26 wells are operated by us. Average net daily production in our Gulf Coast Region at year-end 2025 was 161Boe. At December 31, 2025, we had 429 MBoe of proved reserves in the Gulf Coast region, which represented 1,51% of our total proved reserves. We maintain an acreage position of over 7,003 gross (4,532 net) acres in this region, primarily in Colorado, Newton, and Polk counties.

We are monitoring the production from a new well drilled by Ventex Operating, on acreage in the Segno field of Polk County, Texas where the Company farmed-out its 55% leasehold rights for cash and a 5.53% over-riding royalty interest (ORRI). The well was cased in February 2025 and placed on production in May 2025. Currently, the well is producing 800 Mcfd and 32 Bopd.

The Gulf Coast region has plans to recomplete two producing wells: Sarah F. Wing #80 and the Sarah F. Wing #85 wells in the Segno field of Polk County, Texas, at an expense of approximately $300,000 in total. The Wing #16 was recompleted to the Wilcox A in 2025 at an approximate expense of $500,000. Gas lift valves have been installed with testing currently under way. Other than these recompletions, we currently have no operated wells in the process of being drilled, no waterfloods in the process of being installed and no other related activities of material importance.

Mid-Continent Region

Our Mid-Continent activities are concentrated in central Oklahoma. This region is managed from our office in Oklahoma City, Oklahoma. As of December 31, 2025, we had 677 producing wells (125 net) in the Mid-Continent area, of which 117 wells are operated by us. Principal producing intervals are in the Robberson, Avant, Skinner, Sycamore, Bromide, McLish, Hunton, Mississippian, Oswego, Red Fork, and Chester formations at depths ranging from 1,100 to 10,500 feet. The average net daily production in our Mid-Continent Region in 2025 was 962 Boe. On December 31, 2025, we had 1,401 MBoe of proved reserves in the Mid-Continent area, representing 4.94% of our total proved reserves. We maintain an acreage position of approximately 43,837 gross (10,062 net) acres in this region, primarily in Canadian, Kingfisher, Grant, Major, and Garvin counties.

Our Mid-Continent region is actively participating with third-party operators in the horizontal development of lands that include Company owned interest in several counties in the Scoop and Stack plays of Oklahoma where drilling is primarily targeting reservoirs of the Mississippian, and Woodford formations. In Canadian County, Oklahoma, we have participated with Ovintiv Mid-Continent in the drilling of two 2-mile-long horizontal wells that was spud in early March 2025 and completed in May 2025. Our share of these wells is approximately 3.14% and the total investment is approximately $405,000. We also participated with Devon in Kingfisher County, Oklahoma to drill two 2-mile-long horizontal wells that were spud July 2025 and completed in November 2025. Our share of these wells is approximately 9.95% and total investment of approximately $1,439,000. In 2026, we have plans to participate with Validus Energy II in the drilling of one 3-mile long horizontal well in Grady County, Oklahoma with 3.47% interest, investing roughly $351,000 through completion, one well with Ovintiv Mid-Continent in the drilling of one 2.5-mile long horizontal in Garvin County, Oklahoma with 3.36% interest, investing roughly $291,000 through completion, and one 3-mile long horizontal in Garvin County, Oklahoma with a 2.27% interest, investing roughly $194,000 through completion.

West Texas Region

Our West Texas activities are concentrated in the Permian Basin in Texas. The oil and gas in this basin are produced primarily from five intervals; the Upper and Lower Spraberry, the Wolfcamp, the Strawn, and the Atoka, at depths ranging from 6,700 feet to 11,300 feet. This region is managed from our office in Midland, Texas. As of December 31, 2025, we had 791wells (281 net) in the West Texas area, of which 317 wells are operated by us. Principal producing intervals are in the Spraberry, Wolfcamp, and San Andres formations at depths ranging from 4,200 to 12,500 feet. The average net daily production in our West Texas Region at year-end 2025 was 14,152 Boe. On December 31, 2025, we had 21,544 MBoe of proved reserves in the West Texas area, or 93.54% of our total proved reserves. We maintain an acreage position of approximately 16,838 gross (9,420 net) acres in the Permian Basin in West Texas, primarily in Reagan, Upton, Martin, and Midland counties and believe this acreage has significant resource potential for horizontal drilling in the Spraberry, Jo Mill, and Wolfcamp intervals. We operate a field service group in this region utilizing nine workover rigs, three hot oiler trucks, and one kill truck. Oil field support is provided for drilling and workover operations both to third-party operators as well as for our own operated wells and locations.

During 2024, the Company participated with Double Eagle in the drilling or completion of 15 horizontal wells in Reagan County, Texas with an average of 23% interest, and participating with Apache Corporation in six wells in Upton County, Texas with 51.2% interest. In total, we spent approximately $59.3 million in these 21 horizontals and their associated facilities.

Future drilling activity on our leasehold acreage in West Texas is expected in the next few years as well. In particular, based on activity west of our acreage in Reagan County, and a recent deep test by Double Eagle on our joint leasehold, we anticipate that proposal could soon be put forward for the drilling of between 36 and 45 new horizontals that will target the Wolfcamp “D” pay zone in Reagan County and perhaps an additional test well or two in one or more of the other undeveloped pay horizons. In this future activity, we have the potential to invest in excess of $100 million. In addition, the Company has identified 37 horizontal locations across our acreage in Upton and Martin counties that could be drilled in this same time frame. These additional 37 wells will require an investment of approximately $87 million. In total, therefore, with the $100 million in Wolfcamp “D” development, and the $87 million in 37 other near-term wells expected in the 2026-2027 timeframe, we have the potential to invest approximately $187 million in horizontal drilling in West Texas over the next several years.