# Duhig Rule

**Source:** Buckhead Energy Oil & Gas Encyclopedia (https://www.buckheadenergy.com/learn) — canonical: https://www.buckheadenergy.com/duhig-rule

The Duhig rule is a title-construction doctrine holding that when a grantor conveys land by warranty deed and reserves a fraction of the minerals, but does not own enough minerals to satisfy both the interest granted and the interest reserved, the grantor — not the grantee — bears the shortfall: the grantee takes the full mineral interest the deed warranted to them, and the grantor's reservation is reduced or eliminated to make that possible.

## What problem the Duhig rule solves
Mineral title is fractional, and deeds are drafted by people who do not always check what the grantor actually owns. A recurring accident is over-conveyance: a warranty deed both grants an interest to the buyer and reserves an interest to the seller that, added together, exceed what the seller held. Something has to give — and the question is whose share shrinks. The Duhig rule is the answer most oil and gas states reach.
The rule takes its name from Duhig v. Peavy-Moore Lumber Co., a 1940 Texas Supreme Court decision. Its logic is estoppel by deed: a grantor who warrants title to an interest cannot later claim that same interest through a reservation in the very deed that warranted it away. If the deed cannot give the grantee everything it promised and honor the reservation too, the reservation yields first.

## The classic example
The doctrine is easiest to see with fractions. Suppose the full mineral estate under a tract is 1/1 (100%). Owner A conveys the surface and reserves 1/2 of the minerals to a buyer, B. B now owns the surface plus 1/2 of the minerals; A owns the other 1/2.
Later, B sells to C by warranty deed, purporting to reserve 1/2 of the minerals to himself. Read literally, B has warranted 1/2 to C and reserved 1/2 to himself — a full 1/1 — but B only owned 1/2 to begin with. There is a 1/2 shortfall.
Under Duhig, C receives the full 1/2 the deed warranted, and B's reservation is wiped out — B keeps nothing, because his reservation is the interest that fails. B bears the loss he created by warranting more than he owned. Had B instead conveyed by quitclaim (which warrants nothing), the rule would not apply and B could keep his 1/2 — the warranty is what triggers the estoppel.

## Why the warranty matters
Duhig is a warranty-deed rule. A general warranty deed promises the grantee good title to the interest conveyed and obligates the grantor to defend it; a special warranty makes the same promise limited to claims arising through the grantor. Either way, the grantor has bound himself. A quitclaim deed conveys only whatever the grantor happens to own, with no promise — so a quitclaim over-conveyance simply passes a smaller interest and Duhig has nothing to estop.
This is one reason the type of deed in your chain of title is not a formality. The same words of reservation produce opposite outcomes depending on whether the deed carried a warranty, which is exactly the kind of thing a title opinion is written to catch.

## Where the rule applies — and where it is contested
Texas is the doctrine's home and applies it robustly. Many producing states follow the same estoppel-by-deed reasoning, but the details are not uniform: some courts limit Duhig to two-grant situations, some ask whether the prior outstanding interest was of record, and a few decline the rule where the deed's language shows a contrary intent. Courts also wrestle with harder fact patterns — non-participating royalty reservations, fractions that are not tidy halves, and deeds that reference "an undivided 1/2 of the minerals" versus "1/2 of my interest."
The takeaway for an owner is not to memorize the case law. It is to understand that a reservation written into an old deed does not always mean what it appears to say, and that a break of this kind is resolved by a rule of construction rather than by whoever recorded first.

## What Duhig means for a mineral owner
If your minerals came down a chain with multiple reservations, the fraction you actually own may differ from the fraction the last deed seems to grant. A tract that "looks like" 1/2 to a family may be more — or less — once a Duhig analysis is run against an earlier outstanding reservation. This surfaces most often when an owner tries to lease, sell, or prove ownership and a title examiner reconciles the whole chain rather than the last instrument.
It is also why a serious mineral buyer does its own title work before making a firm offer: the number that matters is your net interest after doctrines like Duhig, the Duhig rule's cousins, and the ordinary arithmetic of fractional ownership are applied. If a buyer quotes a price off the face of one deed without checking the chain, that is a reason to slow down.
None of this requires you to become a title lawyer. It requires knowing that a reservation is not self-executing, that a warranty changes the result, and that when a chain of title has competing reservations, the safe move is to have a qualified oil and gas attorney or landman run it before you rely on a number.

## Frequently asked questions

**What is the Duhig rule in simple terms?**
When a warranty deed grants and reserves more minerals than the grantor actually owns, the grantor loses first: the grantee gets the full interest the deed warranted, and the grantor's reservation is reduced or eliminated to cover the shortfall. The grantor bears the consequence of warranting more than he had.

**Where does the Duhig rule come from?**
The 1940 Texas Supreme Court case Duhig v. Peavy-Moore Lumber Co. Its foundation is estoppel by deed — a grantor who warrants an interest away cannot then claim it back through a reservation in the same deed.

**Does the Duhig rule apply to a quitclaim deed?**
No. Duhig is triggered by the warranty. A quitclaim conveys only whatever the grantor owns and promises nothing, so an over-conveyance by quitclaim simply passes a smaller interest — there is no warranty to estop.

**Do all states follow the Duhig rule?**
Texas applies it strongly and many oil and gas states follow the same reasoning, but not uniformly — some limit it to particular fact patterns, some weigh whether the outstanding interest was of record, and courts split on non-participating royalty reservations and unusual fractions. Have a qualified attorney apply it to your specific chain.

**How does Duhig affect what I can sell?**
It can change your actual net mineral interest relative to what the last deed appears to grant. A careful buyer runs the full chain — Duhig included — before making a firm offer, which is why the interest you own on paper and the interest a title examiner confirms are not always the same number.

## Related terms
- [What a Title Opinion Is](https://www.buckheadenergy.com/title-opinion)
- [Chain of Title](https://www.buckheadenergy.com/chain-of-title)
- [Warranty Deed vs. Quitclaim Deed](https://www.buckheadenergy.com/warranty-deed-vs-quitclaim-deed)
- [How to Prove You Own Mineral Rights](https://www.buckheadenergy.com/how-to-prove-you-own-mineral-rights)
- [Oil & Gas Encyclopedia — all terms](https://www.buckheadenergy.com/learn)

_Educational information only, not legal or tax advice. Buckhead Energy is a direct buyer of oil & gas mineral and royalty interests._