OK, got it. I think JJ bought a bunch of properties using OPM, then convinced retail that they were worth 10 times what he paid, and sold his shares at that price or higher.
It's possible the claims have great value, but it's really unlikely. If the greater profit was from monetizing those claims, JJ would have gone that route. I don't think he's lazy, he's smart and doesn't have a lot of respect, or sympathy, for those who aren't.