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Texas oil lease

Producing

R. MAY B-GUAJILLO UNIT

R. May B-Guajillo Unit is an oil lease in Atascosa County, Texas, operated by Marathon Oil Ef LLC in the Eagleville (Eagle Ford-1) field.

1 well

4,621bbl oil, last 12 months−44% vs prior year
Operator
Marathon Oil Ef LLC
County
Atascosa County
Field
Eagleville (Eagle Ford-1)
RRC lease
01-17935

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Where it sits

This county

Atascosa CountyAtascosaWilsonMedinaKarnesFrioBexarAtascosa County
Atascosa County
Gas, last 12 months
5,673 mcf
Oil in Jul 2026
492 bbl

Production by month

Oil output fell 44% over the last 12 months

  • Oil (bars)
  • Gas (line)
  • Last 12 months
Oil output fell 44% over the last 12 monthsMonthly oil production and gas for R. MAY B-GUAJILLO UNIT, Aug 2023 to Jul 2026. Oil output fell 44% over the last 12 months. 4,621 bbl in the 12 months through Jul 2026, against 8,254 bbl in the 12 months before.Last 12 months: 4,621 bblbbl per monthmcf per month005005001,0001,0001,5001,5002,0002,0002,5002,500Oct 23Jan 24AprJulOctJan 25AprJulOctJan 26AprJul
Oil output fell 44% over the last 12 monthsMonthly oil production and gas for R. MAY B-GUAJILLO UNIT, Aug 2023 to Jul 2026. Oil output fell 44% over the last 12 months. 4,621 bbl in the 12 months through Jul 2026, against 8,254 bbl in the 12 months before.Last 12 monthsbbl per monthmcf per month005005001,0001,0001,5001,5002,0002,0002,5002,500Jan 24JulJan 25JulJan 26Jul

SourceTexas Railroad Commission Production Data Query, through Jul 2026.

Where the gas went

67% of the gas went to a processing plant in the last 12 months

Flaring peaked at 4.2% of the gas in Aug 2025.

  • Processing plant (3)
  • Lease fuel (1)
  • Flared (4)
67% of the gas went to a processing plant in the last 12 monthsShare of R. MAY B-GUAJILLO UNIT gas by disposition code each month, Aug 2023 to Jul 2026. 67% of the gas went to a processing plant in the last 12 months. Flaring peaked at 4.2% of the gas in Aug 2025.Share of the lease’s gas by disposition code, per month0%50%100%Flared 4.2%Oct 23Jan 24AprJulOctJan 25AprJulOctJan 26AprJul
67% of the gas went to a processing plant in the last 12 monthsShare of R. MAY B-GUAJILLO UNIT gas by disposition code each month, Aug 2023 to Jul 2026. 67% of the gas went to a processing plant in the last 12 months. Flaring peaked at 4.2% of the gas in Aug 2025.Share of gas by disposition code0%50%100%Flared 4.2%Jan 24JulJan 25JulJan 26Jul

SourceTexas Railroad Commission Production Data Query, through Jul 2026.

  • Processing plant (3)

    67% · 5,196 mcf

  • Lease fuel (1)

    31% · 2,399 mcf

  • Flared (4)

    2.7% · 209 mcf

2.7% of the gas flared in the last 12 months. 5 months above 3%.

1 well on this lease

Wells on R. MAY B-GUAJILLO UNIT
API numberWell no.Status
42-013-349191HActive

SourceTexas Railroad Commission Wellbore Query.

Buyers and gatherers

Companies named on the Form P-4, by product
CompanyProductRoleShare%FromUntil
Enterprise Crude Oil LLCOilGathers25Jul 1, 2022–
Harvest Midstream CompanyOilGathers25Jul 1, 2022–
Reynolds Energy Transport LLCOilGathers25Jul 1, 2022–
Trafigura Trading LLCOilGathers25Jul 1, 2022–
Marathon Oil Ef LLCCasinghead gasBuys100Jun 19, 2014–
Marathon Oil Ef LLCCasinghead gasGathers100Jun 19, 2014–
Enterprise Crude Oil LLCOilGathers1Sep 1, 2018Jul 1, 2022
Gulfmark Energy, Inc.OilGathers1Sep 1, 2018Jul 1, 2022
Harvest Midstream CompanyOilGathers97Sep 1, 2018Jul 1, 2022
Trafigura Trading LLCOilGathers1Sep 1, 2018Jul 1, 2022

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

Who buys my oilOil price check

63.98 acres on the newest permit

  • 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 R. May B-Guajillo Unit
API numberWell no.Acreson the permit
42-013-349191H63.98

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

Unit decimal checker

What ConocoPhillips told investors it received

Marathon Oil Ef LLC is linked to ConocoPhillips (MRO).
Realized prices reported by ConocoPhillips
QuarterOil$ per bblFiling
Q2 2026$99.40SEC filing
Q1 2026$73.47SEC filing
Q3 2025$66.13SEC filing
Q2 2025$64.23SEC filing
Q1 2025$71.65SEC filing

SourceConocoPhillips quarterly reports, SEC EDGAR, company-wide averages before hedging.

Estimate your royalty

36 months, newest first

Ledger for R. MAY B-GUAJILLO UNIT
MonthOil producedbblOil soldbblGas producedmcfGas soldmcf, codes 2+3FlaredmcfWTI$/bblHenry Hub$/MMBtu
Jul 20264924792411583$80.46$2.89
Jun 20261423320$84.81$3.15
May 20263213281511053$102.13$2.94
Apr 20265815653032163$100.32$2.77
Mar 202600000$91.38$3.04
Feb 202602000$64.51$3.62
Jan 202610611218130$60.04$7.72
Dec 20255795722932122$57.97$4.26
Nov 202511212052362$60.06$3.79
Oct 20257137161,23690818$60.89$3.19
Sep 20258428401,5631,08353$63.96$2.97
Aug 20258618611,8131,15077$64.86$2.91
Jul 20258078061,18774222$68.39$3.20
Jun 202579979594457126$68.17$3.02
May 202543844240224510$62.17$3.12
Apr 202554053789056018$63.54$3.42
Mar 20256026021,05768622$68.24$4.12
Feb 20256816831,49897619$71.53$4.19
Jan 20256976921,8031,16657$75.74$4.13
Dec 20246756752,4971,68348$70.12$3.01
Nov 20246736722,2871,60740$69.95$2.12
Oct 20247667672,3501,73237$71.99$2.20
Sep 20247447461,8651,42430$70.24$2.28
Aug 20248328331,9321,49420$76.68$1.99
Jul 20241,3341,3322,2231,75319$81.80$2.07
Jun 202479479962746410$79.77$2.54
May 202481380843724211$80.02$2.12
Apr 20244104092081057$85.35$1.60
Mar 2024286285144832$81.28$1.49
Feb 20242882911251180$77.25$1.72
Jan 20245445401831701$74.15$3.18
Dec 202311411737350$71.90$2.52
Nov 20234254245335061$77.69$2.71
Oct 20234754775935612$85.64$2.98
Sep 20237367361,1881,1169$89.43$2.64
Aug 20237147118708282$81.39$2.58

Flared above 3%

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

OperatorMarathon Oil Ef LLCFieldEagleville (Eagle Ford-1)CountyAtascosa County

Marathon Oil Ef LLC in Atascosa County

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