Can a purchaser of mineral rights state they're buying X number of nma and then following a title confirmation pay for a lower number nma without notifying the owner so they could rescind or re-negotiate the sale.
Also is the 60 day title confirmation period ever negotiable. Thanks
The short answer is that it depends on the language of the agreement.
Is there a clause that if the seller owns less than the amount represented in the agreement, then the seller gets paid for the lesser amount of acres (or, the contrary, as you have suggested, that the agreement is or may be automatically cancelled without notice or opportunity to cure)? The buyer could sue the seller for fraudulently misrepresenting the number of acres, depending on the agreement or lack thereof as the case may be.
As to negotiable time periods, again, it depends on the circumstances. You say "ever." I would have to say that there are times when anything can be negotiable. Who is buying? Who is selling? Does the buyer have to drill within 60 days or else lose another part of the lease? Is the buyer trying to get his foot in the door and sign up the first parcel of a larger lease that will take a year to sign up all of the mineral owners? It would make a difference.
If you would like to send me the agreement, perhaps I could be more specific.