(a) For purposes of the coverage required by this subchapter, “uninsured motor vehicle,” subject to the terms of the coverage, is considered to include an insured motor vehicle as to which the insurer providing liability insurance is unable because of insolvency to make payment with respect to the legal liability of the insured within the limits specified in the insurance.
(b) The commissioner may, in the policy forms filed under Subchapter B, Chapter 2301, allow “uninsured motor vehicle” to be defined or, in policy forms adopted under Article 5.06, define “uninsured motor vehicle,” to exclude certain motor vehicles whose operators are in fact uninsured.