Do they still own them?
If so and there is drilling they will contact your great grandparents to sign a lease.
it is very possible if they owned them at one time, they might have sold them with a property or sold them separately without the property.
If it is your great grandparents, there is a real possibility they never owned them as at one time the state owned most mineral rights.
First of all, read over the agreement that your great grandparents have. If you do not understand it, you might contact the company itself or find yourself a consultant who will be able to help you understand the paperwork.
Lynn911 Dallas Realtor & Consultant
Multimillion Dollar Sales Producer
http://www.lynn911.com 100's of Dallas homes listed for sale or lease
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