Tex. Natural Resources Code § 51.020

(a) On presentation of proper proof, money paid in good faith to a fund in the State Treasury for public land or by a lessee of public land or minerals to which the fund is not entitled may be offset or credited by the commissioner against other sums owing or shall be refunded by the comptroller in the following instances:

(1) if an error is made in good faith and the refund, stating to whom payment is to be made, is supported by the official signature of the commissioner or the attorney general;

(2) if the payment is made according to law but title cannot issue or possession cannot pass because of a conflict in boundaries, an erroneous sale, an erroneous lease, or other cause;

(3) if there is a sale of leased land;

(4) if lease money is paid on a previous forfeited sale and the sale has been reinstated and the interest paid;

(5) if erroneous timber sales or leases have been made;

(6) if overpayments have been made in final payments to the comptroller because of decreased acreage or other cause;

(7) if reduction has been made in acreage of timber sold or leased; or

(8) if payments are made in good faith by claimants of land where the applicants have no right to purchase the land as revealed by investigation of title.

(b) After specific appropriations are made according to law, refunds shall be paid from the funds to which the payments have been credited.

(c) Any claim for refund except a refund covered by Subdivision (1) of Subsection (a) of this section shall be certified by the commissioner, verified by the affidavit of the claimant, and approved by the attorney general as to the correctness and as to whom the refund is due.

(d) In the event of a failure of title or right of possession, money paid by any purchaser or lessee who subsequently sells the land or assigns the lease shall be refunded to the person on whom the loss falls.