Patent

A patent is the document by which the United States passes title to public land into private hands. In mining, a mineral patent turns a located mining claim or mill site into private land.

What a mineral patent conveys

BLM describes a patented mining claim as "one for which the Federal Government has passed its title to the claimant, giving the claimant exclusive title to the locatable minerals and, in most cases, the surface and all resources." Note the words "in most cases": a patent does not always carry the surface.

An unpatented mining claim is different. BLM describes it as a right of possession and a right "to develop and extract a discovered, valuable, mineral deposit," and says that right "does not include exclusive surface rights." Title to the land stays with the United States.

What can be patented

• Lode claims (30 U.S.C. 29)
• Placer claims (30 U.S.C. 37). Where a vein is not known to exist inside a placer claim, the placer patent conveys "all valuable mineral and other deposits within the boundaries thereof."
• Mill sites, up to five acres each (30 U.S.C. 42)
• Not tunnel sites. BLM states that mineral patents "can be issued for lode claims, placer claims, and mill sites but not for tunnel sites."

How a patent was obtained

Under 30 U.S.C. 29 and 43 CFR part 3860, the applicant:

• Had the claim surveyed by a U.S. mineral surveyor appointed by BLM, with the boundaries "distinctly marked by monuments on the ground" (43 CFR 3861.1-1). The claimant chose the surveyor from BLM's roster and paid for the survey.
• Posted a copy of the plat and a notice of the application in a conspicuous place on the claim, and filed an affidavit of two persons that it was posted
• Showed that at least $500 worth of labor or improvements had been made on each location
• Had notice of the application published for 60 days in the newspaper nearest the claim. Anyone with a conflicting claim had to file an adverse claim within that period.
• Paid the purchase price: $5 per acre for lode claims and $2.50 per acre for placer claims. Mill sites were paid at the lode rate, or at the placer rate when tied to a placer claim.

The moratorium

Since October 1, 1994, Congress has barred BLM from spending appropriated funds to accept or process new mineral patent applications. BLM's patents page says: "Until the moratorium is lifted or otherwise expires, the BLM will not accept any new patent applications." The restriction is not permanent law. It is renewed each year in the Interior appropriations act, most recently in Public Law 119-74 (2026), section 404. Applications filed on or before September 30, 1994 that had met every requirement by that date are excepted.

Why patents matter in mineral title research

• Patented claims are private land. They are bought, sold, taxed, and inherited like other real property, and their title runs through county records after the patent issues.
• The patent itself, the mineral survey plat, and the field notes are the starting point of that chain of title. BLM's General Land Office Records site holds images of federal land title records and survey plats, and the master title plat for a township shows current land status.
• Unpatented mining claims inside or next to old patents are common, so the boundaries of the patented ground have to be known before the open federal ground around it can be understood.