Tex. Bus. Orgs. Code § 22.509

On or after the validation effective time, unless determined otherwise in an action brought under Section 22.512 and subject to Section 22.502(b), each defective corporate act ratified in accordance with this subchapter may not be considered ineffective, void, or voidable as a result of the failure of authorization described by the resolutions adopted under Sections 22.503 and 22.504, and the effect shall be retroactive to the time of the defective corporate act.