Four Missouri elk hunters used [a stepladder] to climb over an invisible corner from one parcel of Bureau of Land Management terrain to another. They never touched a toe on two adjacent swaths of private property marked by “No Trespassing” signs.

But to the owner of that property, a North Carolina multimillionaire whose portfolio includes 22,000 acres of this game-rich mountain, the hunters’ aerial corner-cross was trespassing all the same. Whether he is correct — and the extent to which private property rights can thwart the public’s ability to access its land on thousands of similar corners — is now being weighed by the U.S. Court of Appeals for the 10th Circuit in Denver.