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Royalty Clerk

Texas operator · RRC P-5 100156

Castlerock Ef Operating LLC

Castlerock Ef Operating LLC runs 13 producing leases in 2 Texas counties. The Railroad Commission shows 506,492 barrels of oil and 814,198 mcf of gas in the 12 months through Jul 2026.

Operator dossier · 2 counties

506,492bbl oil, last 12 months−55% vs prior year
Producing leases
13of 17 on record
Counties
2
Biggest county
McMullen County
Biggest field
Eagleville (Eagle Ford-1)

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Where they work

fewermore

LA Salle County: 5 producing leasesMcMullen County: 8 producing leasesMcMullenDuvalAtascosaWebbFrioJim WellsLive OakMcMullenLA Salle
2 counties with producing leasesClick a county to open it
Gas, last 12 months
814,198 mcf
RRC operator no.
100156
Leases on record
17
Data through
Jul 2026

Production

Five years of Castlerock Ef Operating LLC output

Monthly totals across every lease the Railroad Commission lists under this operator. When the operator buys or sells leases, its total moves with them.

Oil output from Castlerock Ef Operating LLC fell 55% over the last 12 months

506k bbl in the 12 months through Jul 2026, against 1.1M bbl in the 12 months before. Peak month: Oct 2024, 158k bbl.

Oil output from Castlerock Ef Operating LLC fell 55% over the last 12 months506k bbl in the 12 months through Jul 2026, against 1.1M bbl in the 12 months before. Peak month: Oct 2024, 158k bbl.Oil, bbl per month050k100k150k200kPeak 158k (Oct 24)23.2k20222023202420252026
Oil output from Castlerock Ef Operating LLC fell 55% over the last 12 months506k bbl in the 12 months through Jul 2026, against 1.1M bbl in the 12 months before. Peak month: Oct 2024, 158k bbl.Oil, bbl per month050k100k150k200kPeak 158k (Oct 24)23.2k'22'23'24'25'26

Gas output from Castlerock Ef Operating LLC fell 46% over the last 12 months

814k mcf in the 12 months through Jul 2026, against 1.5M mcf in the 12 months before. Peak month: Oct 2024, 174k mcf.

Gas output from Castlerock Ef Operating LLC fell 46% over the last 12 months814k mcf in the 12 months through Jul 2026, against 1.5M mcf in the 12 months before. Peak month: Oct 2024, 174k mcf.Gas, mcf per month050k100k150k200kPeak 174k (Oct 24)37.6k20222023202420252026
Gas output from Castlerock Ef Operating LLC fell 46% over the last 12 months814k mcf in the 12 months through Jul 2026, against 1.5M mcf in the 12 months before. Peak month: Oct 2024, 174k mcf.Gas, mcf per month050k100k150k200kPeak 174k (Oct 24)37.6k'22'23'24'25'26

SourceTexas Railroad Commission, Production Data Query, summed over every lease reported under operator 100156. Reported through Jul 2026, file dated Sep 18, 2026. The newest month is often revised as operators file late.

Leases

Castlerock Ef Operating LLC leases, biggest first

Find the lease printed on your statement. Filter by county, sort by output or by change over the year, and open any lease for its ledger.

Showing 13 of 13.

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SourceTexas Railroad Commission, Production Data Query. Ranked by an approximate value of last-12-month output, so oil and gas wells sort together.

Where they work

Counties and fields where Castlerock Ef Operating LLC produces

Every county and field links to the others operating there, so you can see who else is drilling around your lease.

Counties, by Castlerock Ef Operating LLC oil

McMullen County leads

  1. McMullen County8 producing leases358kbbl
  2. LA Salle County5 producing leases148kbbl

Fields, by Castlerock Ef Operating LLC oil

Eagleville (Eagle Ford-1) leads

  1. Eagleville (Eagle Ford-1)13 producing leases · District 01 · Field 27135700506kbbl

Recent drilling permits for Castlerock Ef Operating LLC

How to read the statement

How to read a Castlerock Ef Operating LLC royalty statement

Every operator lays out its stub differently, but the same seven parts are on all of them. This guide is a template, with what public records tell us about Castlerock Ef Operating LLC added where they help. We have not catalogued Castlerock Ef Operating LLC’s exact layout yet.

  1. The header: who paid you, and for which check

    Look for the payor name, your owner number, the check number and the check date. Keep the owner number: every call or letter to the operator starts with it.

    What we knowCastlerock Ef Operating LLC is Railroad Commission operator 100156. The name on your check may be a parent company or a payment subsidiary.

  2. The property line: which lease this is

    Each lease you own in gets its own block, named as the operator names it. That name can be shorter than the state's, or carry a suffix such as a well number or unit letter.

    What we knowCastlerock Ef Operating LLC runs 13 producing leases across 2 counties, so one check can list many properties. Find yours in the table above by name, or search for the name printed on the stub.

  3. Product and volume: barrels, mcf, and the month

    The stub shows the production month (the production month, not the check month), the product and your share of the volume. Divide your volume by your decimal to get the lease total, then compare it with the lease page.

    What we knowFor example, open CRX YBAR, Y-BAR or Y-BAR 170H UNIT and read the “oil sold” and “gas sold” columns.

  4. Price: what the operator says it got

    Oil is usually close to the WTI benchmark for the month. Gas prices vary widely: they depend on where the gas is sold and on what the operator subtracts before it reports a price.

  5. Deductions: gathering, compression, processing

    Costs taken after the well. Some leases allow them and some do not; your lease and division order say which. A deduction that appears in one month and not the next is worth a question.

    What we knowAbout 65% of the gas Castlerock Ef Operating LLC reported in the last 12 months went straight into pipelines rather than to a processing plant. A processing fee on that gas is worth asking about.

  6. Taxes: severance and ad valorem

    Texas severance tax is taken from your share: 4.6% of oil value and 7.5% of gas value at market. Ad valorem tax may also appear. The rate on your stub should match these.

  7. Net: gross, minus deductions and taxes, times your share

    Check the arithmetic: volume times price gives gross value, then subtract deductions and taxes. If the net does not match your check, or a month is missing, that is the first thing to ask about.

    What we know10% of the gas Castlerock Ef Operating LLC reported was flared or vented. Flared gas pays no royalty, so a lease that flares heavily will show a smaller gas volume on your stub than on the state's production line.

At a glance

Castlerock Ef Operating LLC

RRC operator number (P-5)
100156
Producing leases
13
Counties
2
Biggest county
McMullen County
Oil, last 12 months
506,492 bbl
Gas sent to plants
0.0%
Gas sold to pipelines
65%
Gas flared or vented
10%

Owner relations

Who to call at Castlerock Ef Operating LLC

We have not yet added Castlerock Ef Operating LLC’s owner relations phone, mailing address or online portal. It is usually printed at the top or bottom of your statement. The Railroad Commission also holds an address for the operator under number 100156.

When there is something to ask

We write the question for you, with the numbers behind it, and a letter you can send.
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