Tex. Property Code § 13.001: VALIDITY OF UNRECORDED INSTRUMENT.

(a) A conveyance of real property or an interest in real property or a mortgage or deed of trust is void as to a creditor or to a subsequent purchaser for a valuable consideration without notice unless the instrument has been acknowledged, sworn to, or proved and filed for record as required by law.

(b) The unrecorded instrument is binding on a party to the instrument, on the party's heirs, and on a subsequent purchaser who does not pay a valuable consideration or who has notice of the instrument.

(c) This section does not apply to a financing statement, a security agreement filed as a financing statement, or a continuation statement filed for record under the Business & Commerce Code.

Acts 1983, 68th Leg., p. 3495, ch. 576, Sec. 1, eff. Jan. 1, 1984. Amended by Acts 1989, 71st Leg., ch. 162, Sec. 4, eff. Sept. 1, 1989.