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Texas oil lease

Producing

MOBIL-COOK

Mobil-Cook is an oil lease in Upton County, Texas, operated by Extex Operating Company in the Heluma, East (Devonian) field.

4 wells

4,759bbl oil, last 12 months−18% vs prior year
Operator
Extex Operating Company
County
Upton County
Field
Heluma, East (Devonian)
RRC lease
7C-06330

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Where it sits

This county

Upton CountyUptonMidlandCraneGlasscockReaganEctorUpton County
Upton County
Gas, last 12 months
17,013 mcf
Oil in Jul 2026
396 bbl

Production by month

Oil output fell 18% over the last 12 months

  • Oil (bars)
  • Gas (line)
  • Last 12 months
Oil output fell 18% over the last 12 monthsMonthly oil production and gas for MOBIL-COOK, Aug 2023 to Jul 2026. Oil output fell 18% over the last 12 months. 4,759 bbl in the 12 months through Jul 2026, against 5,815 bbl in the 12 months before.Last 12 months: 4,759 bblbbl per monthmcf per month002501,0005002,0007503,0001,0004,0001,2505,000Oct 23Jan 24AprJulOctJan 25AprJulOctJan 26AprJul
Oil output fell 18% over the last 12 monthsMonthly oil production and gas for MOBIL-COOK, Aug 2023 to Jul 2026. Oil output fell 18% over the last 12 months. 4,759 bbl in the 12 months through Jul 2026, against 5,815 bbl in the 12 months before.Last 12 monthsbbl per monthmcf per month002501,0005002,0007503,0001,0004,0001,2505,000Jan 24JulJan 25JulJan 26Jul

SourceTexas Railroad Commission Production Data Query, through Jul 2026.

Where the gas went

All of the gas went to a processing plant in the last 12 months

All of the gas went to a processing plant in the last 12 monthsShare of MOBIL-COOK gas by disposition code each month, Aug 2023 to Jul 2026. All of the gas went to a processing plant in the last 12 months.Share of the lease’s gas by disposition code, per month0%50%100%Oct 23Jan 24AprJulOctJan 25AprJulOctJan 26AprJul
All of the gas went to a processing plant in the last 12 monthsShare of MOBIL-COOK gas by disposition code each month, Aug 2023 to Jul 2026. All of the gas went to a processing plant in the last 12 months.Share of gas by disposition code0%50%100%Jan 24JulJan 25JulJan 26Jul

SourceTexas Railroad Commission Production Data Query, through Jul 2026.

Who has run this lease

The operator changed once, most recently in Feb 2021

Operators of this lease over timeLegacy Reserves Operating LP, Jan 2020 to Jan 2021; Extex Operating Company, Feb 2021 to Jul 20262020202120222023202420252026Changed Feb 2021Legacy Reserves Operating LPJan 2020 to Jan 2021Extex Operating CompanyFeb 2021 to now
Operators of this lease over timeLegacy Reserves Operating LP, Jan 2020 to Jan 2021; Extex Operating Company, Feb 2021 to Jul 20262020202120222023202420252026Changed Feb 2021Legacy Reserves Operating LPJan 2020 to Jan 2021Extex Operating CompanyFeb 2021 to now

SourceTexas Railroad Commission Production Data Query, through Jul 2026.

4 wells on this lease

Wells on MOBIL-COOK
API numberWell no.Status
42-461-301461 UActive
42-461-301722 UActive
42-461-302063Active
42-461-303905Active

SourceTexas Railroad Commission Wellbore Query.

Buyers and gatherers

Companies named on the Form P-4, by product
CompanyProductRoleShare%FromUntil
Echo Canyon Energy Prd Sply, LLCOilGathers100Sep 1, 2026–
Mv Purchasing, LLCOilGathers100Jul 1, 2026Sep 1, 2026
Dcp Operating Company, LPCasinghead gasGathers100Apr 1, 2017Jul 1, 2026
Dcp Operating Company, LPCasinghead gasBuys100Apr 1, 2017Jul 1, 2026
Plains Marketing, L.p.OilGathers100Jun 1, 2017Jul 1, 2026

SourceRailroad Commission Form P-4 file, Sep 24, 2026 (source).

Who buys my oilOil price check

240 acres on the newest permit

  • Good to know

    The wells on this lease state different acreage

    The permits state between 240 and 320 acres. Use the acres from your own division order for the well you are paid on.

  • Worth asking

    A Rule 37 case is listed

    The RRC permit records list a Rule 37 case. This does not establish your royalty share. Ask for the permit and unit plat for your well.

Check your decimal on this lease
Permits for Mobil-Cook
API numberWell no.Acreson the permit
42-461-301461 U240
42-461-302063320
42-461-302063 U320
42-461-301722 U–
42-461-302684 U–
42-461-303905–

SourceRailroad Commission drilling permits, Oct 3, 2026 (source 1, source 2).

Unit decimal checker

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36 months, newest first

Ledger for MOBIL-COOK
MonthOil producedbblOil soldbblGas producedmcfGas soldmcf, codes 2+3FlaredmcfWTI$/bblHenry Hub$/MMBtu
Jul 2026Extex Operating396181000$80.46$2.89
Jun 2026Extex Operating426544000$84.81$3.15
May 2026Extex Operating524356000$102.13$2.94
Apr 2026Extex Operating504366000$100.32$2.77
Mar 2026Extex Operating5887342,5192,5190$91.38$3.04
Feb 2026Extex Operating6035512,8742,8740$64.51$3.62
Jan 2026Extex Operating4353663,8783,8780$60.04$7.72
Dec 2025Extex Operating2011813,7573,7570$57.97$4.26
Nov 2025Extex Operating2773643,9853,9850$60.06$3.79
Oct 2025Extex Operating296364000$60.89$3.19
Sep 2025Extex Operating196185000$63.96$2.97
Aug 2025Extex Operating313365000$64.86$2.91
Jul 2025Extex Operating443369000$68.39$3.20
Jun 2025Extex Operating4295453,0443,0440$68.17$3.02
May 2025Extex Operating460184000$62.17$3.12
Apr 2025Extex Operating3915434,6444,6440$63.54$3.42
Mar 2025Extex Operating3855504,8084,8080$68.24$4.12
Feb 2025Extex Operating209367000$71.53$4.19
Jan 2025Extex Operating909726000$75.74$4.13
Dec 2024Extex Operating787539000$70.12$3.01
Nov 2024Extex Operating1,0571,0983,4833,4830$69.95$2.12
Oct 2024Extex Operating3911824,8574,8570$71.99$2.20
Sep 2024Extex Operating2303623,7733,7730$70.24$2.28
Aug 2024Extex Operating12406076070$76.68$1.99
Jul 2024Extex Operating1181798058050$81.80$2.07
Jun 2024Extex Operating2371844,2134,2130$79.77$2.54
May 2024Extex Operating2071781,0091,0090$80.02$2.12
Apr 2024Extex Operating2673652,2842,2840$85.35$1.60
Mar 2024Extex Operating2271834,6184,6180$81.28$1.49
Feb 2024Extex Operating1681822,7172,7170$77.25$1.72
Jan 2024Extex Operating147177000$74.15$3.18
Dec 2023Extex Operating142186000$71.90$2.52
Nov 2023Extex Operating1240000$77.69$2.71
Oct 2023Extex Operating139161000$85.64$2.98
Sep 2023Extex Operating112178000$89.43$2.64
Aug 2023Extex Operating149359000$81.39$2.58

SourceTexas Railroad Commission Production Data Query, through Jul 2026. Prices: EIA, through Aug 2026. Updated Oct 2, 2026.

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Nearby

This lease belongs to

OperatorExtex Operating CompanyFieldHeluma, East (Devonian)CountyUpton County

Extex Operating Company in Upton County

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Heluma, East (Devonian) field

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