United States v. Locke

The Federal Land Policy and Management Act (FLPMA) required holders of pre-existing unpatented mining claims to register with the BLM and to make an annual filing "prior to December 31" each year, with noncompliance deemed abandonment under the statute. Several mining-claim holders (plaintiffs) with multimillion-dollar Nevada claims registered on time but submitted their annual filing on December 31 itself — one day after the statutory deadline — after allegedly receiving misleading guidance from a BLM employee; the BLM declared their claims abandoned, and the district court granted summary judgment for the claimholders on a substantial-compliance theory, prompting Supreme Court review of the takings and due-process claims.