CHALLENGER UNIT B
CHALLENGER UNIT B is a Texas oil lease in Karnes County, Railroad Commission district 02, operated by Marathon Oil Ef LLC. It has 9 wellbores on file with the Commission. Reported production runs from February 2013 to August 2026, totalling 2,602,442 barrels. The lease is currently producing. Fitting a decline curve to that history and pricing the remaining production at today's forward curve values the whole lease — a 100% undivided interest — at about $1.5M, with roughly $965K expected over the next twelve months. An individual royalty owner receives their own decimal interest times that figure. Over the last twelve months on file it averaged 2,310 barrels a month, about 257 per wellbore. Its strongest month on the record we hold was May 2016, at 22,198 barrels. In our own backtest, leases producing at this rate are forecast to within about 17% of what they went on to produce, and that measured error is the range shown on the page rather than a confidence of our own devising.
Key facts about CHALLENGER UNIT B
- Who operates CHALLENGER UNIT B?
- CHALLENGER UNIT B is operated by Marathon Oil Ef LLC, Railroad Commission of Texas operator number 525398.
- Where is CHALLENGER UNIT B?
- CHALLENGER UNIT B is a Texas oil lease in Karnes County, Texas, in Railroad Commission district 02. Its Railroad Commission lease number is 10434.
- Is CHALLENGER UNIT B still producing?
- CHALLENGER UNIT B is currently producing. The most recent month of production reported to the Railroad Commission of Texas for CHALLENGER UNIT B is August 2026.
- How much has CHALLENGER UNIT B produced?
- CHALLENGER UNIT B has reported 2,602,442 barrels of oil (bbl) to the Railroad Commission of Texas between February 2013 and August 2026, from 9 wellbores.
- How much is CHALLENGER UNIT B worth?
- The remaining production from CHALLENGER UNIT B is estimated to be worth about $1.5M in total as of 27 August 2026, within a range of $1.3M to $1.8M. That figure is the whole lease, undivided — not any one owner's share. A royalty interest in CHALLENGER UNIT B is a fraction of it. The estimate fits an Arps decline curve to the production CHALLENGER UNIT B has already reported, prices the remaining production at the current forward strip, and discounts it at 12% a year. The figure shown for CHALLENGER UNIT B is an estimate of value, not an offer and not an appraisal.
- How much income does CHALLENGER UNIT B generate in a year?
- CHALLENGER UNIT B is forecast to net about $965K across the whole undivided lease over the twelve months following 27 August 2026, before income tax. A royalty owner in CHALLENGER UNIT B receives a fraction of that, set by the decimal interest printed on their check stub.
Lease record
| Operator | Marathon Oil Ef LLC |
|---|---|
| Field | Eagleville (Eagle Ford-2) |
| County | Karnes County, Texas |
| RRC district | 02 |
| Lease number | 10434 |
| Wellbores | 9 |
| Reported production | 2,602,442 bbl |
| First reported | |
| Last reported | |
| Estimated royalty value | $1.5M |
Where CHALLENGER UNIT B sits
Source: Railroad Commission of Texas lease production records, complete through . Figures on this page were computed on .
Production figures are as reported to the Railroad Commission of Texas. The value shown is an estimate produced by fitting a decline curve to that reported history; it is not an offer or an appraisal. How this estimate is calculated.