## Facts

- Lucky McUranium Corporation conducted uranium reconnaissance on federal public-domain land in Arizona’s Artillery Peak Mining District and detected geologic “anomalies” suggesting possible mineralization.
- Lucky monumented and posted 200 unpatented lode mining claims (about 4,000 acres), drilled a 10-foot hole on each claim, and recorded notices under Arizona mining statutes.
- Lucky had not discovered “minerals in place”; the trial court found insufficient evidence of a valid mineral discovery.
- Geomet Exploration, Ltd. later entered certain areas within the boundaries of Lucky’s recorded claims, began drilling, and did so with knowledge of Lucky’s recorded locations.
- Geomet believed Lucky’s locations were defective because there was no mineral discovery and Lucky was not in actual occupancy of the areas Geomet entered.
- Lucky sued in a possessory action for damages, exclusive possession, and a permanent injunction against Geomet’s alleged trespass.
- The trial court granted Lucky exclusive possession and a permanent injunction extending to all claims, reasoning that strict actual-occupancy requirements should be relaxed given modern exploration economics and finding Geomet acted in “bad faith.”
- The court of appeals affirmed.

## Issues

1. Whether, before mineral discovery, the doctrine of *pedis possessio* should be modified to allow constructive possession of contiguous, unoccupied mining claims based on partial work within the claim block.
2. Whether a subsequent peaceable, open entrant may acquire superior pre-discovery possessory rights on unoccupied ground within a prior locator’s recorded but undiscovered claim block.
3. Whether knowledge of earlier recorded claims establishes “bad faith” that bars a later entrant from asserting *pedis possessio* rights.

## Decision

- The Arizona Supreme Court vacated the court of appeals’ decision and reversed the trial court’s broad grant of exclusive possession and injunction.
- The court held that *pedis possessio* was not expanded to constructive possession over a block of contiguous, unoccupied claims before discovery.
- Lucky’s pre-discovery protection was limited to ground it actually occupied and diligently worked toward discovery.
- Geomet’s peaceable, open entry onto unoccupied portions could support Geomet’s own possessory rights if accompanied by actual occupancy and a diligent search for minerals.
- Geomet’s knowledge of Lucky’s recorded claims, without more, did not constitute disqualifying bad faith.

## Legal Principles

- Pre-discovery possessory protection on federal public-domain mineral lands is governed by *pedis possessio*, which requires actual physical occupancy and diligent work toward discovery.
- Recordation, monumenting, geophysical indications, or partial drilling do not confer constructive possession of unoccupied ground before discovery.
- The federal mining law policy keeps unoccupied public land open to exploration until discovery or actual, diligent occupancy establishes priority on specific ground.
- A later entrant who enters peaceably and openly onto unoccupied ground is not barred from asserting possessory rights merely because the entrant knew of earlier recorded but undiscovered and unoccupied locations.

## Conclusion

The court limited pre-discovery protection under *pedis possessio* to areas of actual occupancy coupled with diligent work toward discovery, rejecting constructive possession over contiguous, unoccupied claims and narrowing the injunction to exclude ground Lucky did not physically occupy and work.


Geomet Expl. Ltd. v. Lucky McUranium Corp., 124 Ariz. 55, 601 P.2d 1339 (Ariz. 1979)