There's a little something in American jurisprudence called adverse possession. Adverse possession says that if you openly and visibly occupy land belonging to another, with the owners full knowledge and without his attempt to evict you, the land belongs to you. You can find out more about adverse possession here
The statute of limitations for adverse possession varies from State to State. In Nevada it's three years. Cliven Bundy has not paid BLM fees for 20 years, since 1993. That the government was aware of this is obvious from the fact that, in 1998, they filed court action against Mr. Bundy. Since they knew of the situation and did nothing about it, the government, assuming they even owned the land, ceded it to Cliven Bundy in 2001.
Of course, in 2001, no one knew that in 2013 Harry Reid and Warren Buffet would want the land to sell to a Communist Chinese company for their personal enrichment and to foster President Obama's ignorance inspired choom pipe dream of a solar Boulder Dam in the Nevada desert.
Harry Reid recently said, "We can't have an American people that violate the law and then just walk away from it. So it's not over," I agree Harry. So we're coming after you and Buffet for breaking the law!
UPDATE: Issa to investigate Reid/Obama complicity in Bundy Ranch scandal. http://visiontoamerica.com/17289/issa-launches-federal-investigation-into-obamareid-involvement-in-blm-land-grab/
UPDATE: Reid/Obama try Gestapo tactics in Bunkerville. http://nationalreport.net/multiple-militia-members-arrested-bundy-ranch-charged-domestic-terrorism/