It may help to recall that these confidentiality agreements include 5-year prohibitions on using company information to the disadvantage of LBSR.  Therefore, any potential partner who has signed such an agreement would not be able to "lap up" claims for five years. 

Looking back a few years, a period when mining was really in the dumps, JB claimed to have refused two or more offers for confidentiality agreements, because those people wanted only 2-year terms.  in which case it would be very much easier to wait out the company, and lap up whatever they found attractive that was not already claimed. 

While JB may not have been too concerned about that in regards to existing claims, which can be rolled over, I think he was very concerned about claims he wanted, but could not yet afford.  ...don't know if these are the same claims just aquired, or others.  Even so, I know there is much more in the Tombstone caldera that is of interest to the company, and not yet in the stable.  Hence, the need for CAs - everything they know is disclosed about the area, not just about claims held at present.