Tex. Election Code § 142.009: PETITION TO BE CIRCULATED AFTER PRIMARY.

A signature on a candidate's petition is invalid if the signer:

(1) signed the petition on or before general primary election day or, if a runoff primary is held for the office sought by the candidate, on or before runoff primary election day; or

(2) voted in the general or runoff primary election of a political party that made a nomination, at either primary, for the office sought by the candidate.

Acts 1985, 69th Leg., ch. 211, Sec. 1, eff. Jan. 1, 1986.