## Facts

- Prior grantors conveyed defendants a defeasible term mineral interest in an undivided fractional share of minerals under a Kansas tract, subject to a special limitation ending the interest if production or operations ceased for a stated period.
- Donald D. Edmonston later acquired the surface estate and the grantors’ retained interests, including the reversion that would take effect if defendants’ defeasible mineral interest terminated.
- A well previously drilled on part of the relevant lands produced and was later plugged and abandoned in 1973; no subsequent producing well was drilled or located on the specific quarter-section implicated in the dispute.
- The Kansas Corporation Commission (KCC) had entered a unitization order pooling lands into a unit and providing that production within the unit would be treated as production on included tracts for certain purposes.
- After 1973, production continued somewhere within the unit, but not on the specific lands burdened by defendants’ defeasible term mineral interest.
- Edmonston filed a quiet title action asserting defendants’ mineral interest terminated by its deed terms; defendants asserted unit production preserved their interest.
- The federal appellate court certified controlling questions of Kansas law to the Kansas Supreme Court.

## Issues

1. Whether a KCC unitization order and production elsewhere in the unit preserves a deed-created defeasible term mineral interest when the deed conditions continuation on production or operations on the burdened land.
2. Whether the “production anywhere in the unit is production on all tracts” concept applies to defeasible term mineral interests, as opposed to oil and gas leases and royalty arrangements.

## Decision

- The court answered the certified questions in substance for Edmonston.
- A KCC unitization order did not extend or preserve defendants’ defeasible term mineral interest once production and operations ceased on the specific lands burdened by that interest.
- Continued production elsewhere in the unit was legally insufficient to satisfy the deed’s special limitation.
- Defendants’ defeasible term mineral interest terminated by its own terms, and Edmonston’s reversionary interest became possessory.

## Legal Principles

- A defeasible term mineral interest is a real property estate that ends automatically upon the occurrence of a stated condition; courts apply the granting instrument’s special limitation as written.
- Conservation-based unitization orders are construed according to their text and purpose and will not be read to alter private deed limitations absent clear statutory or regulatory direction.
- The rule treating unit production as tract production commonly applies in the lease and royalty context and does not automatically govern separately granted mineral estates subject to deed-created termination provisions.
- Regulatory action cannot enlarge a privately created determinable mineral estate beyond the scope of the deed without explicit authority.

## Conclusion

Kansas law gives controlling effect to deed language creating a defeasible term mineral interest; unit-wide production under a KCC unitization order does not prevent termination when the deed requires production or operations on the specific burdened land, so the mineral interest expires and the reversion vests in the successor owner.


Edmonston v. Home Stake Oil & Gas Corp., 762 P.2d 176 (Kan. 1988)