Brown, Ltd, et al. v. Sheppard, 282 S.W.3d 419 (Tex. Sup. Ct. 2008)

(oil well lease contained in pool of producing properties expired and legal issue was whether expiration of lease removed the minerals from the pool and bars costs incurred before termination; trial court determination that is did reversed – pooling agreement did not depend on continuation of underlying leases, and equitable right of reimbursement for improvements not necessarily extinguished by termination of lease).