Tex. Finance Code § 36.302

(a) A proof of claim must be in writing, be signed by the claimant, and include:

(1) a statement of the claim;

(2) a description of the consideration for the claim;

(3) a statement of whether collateral is held or a security interest is asserted against the claim and, if so, a description of the collateral or security interest;

(4) a statement of any right of priority of payment for the claim or other specific right asserted by the claimant;

(5) a statement of whether a payment has been made on the claim and, if so, the amount and source of the payment, to the extent known by the claimant;

(6) a statement that the amount claimed is justly owed by the bank in liquidation to the claimant; and

(7) any other matter that is required by the court.

(b) The receiver may designate the form of the proof of claim. A proof of claim must be filed under oath unless the oath is waived by the receiver. A proof of claim filed with the receiver is considered filed in an official proceeding for purposes of Chapter 37, Penal Code.

(c) If a claim is founded on a written instrument, the original instrument, unless lost or destroyed, must be filed with the proof of claim. After the instrument is filed, the receiver may permit the claimant to substitute a copy of the instrument until the final disposition of the claim. If the instrument is lost or destroyed, a statement of that fact and of the circumstances of the loss or destruction must be filed under oath with the claim.