(a) “Medicare supplement benefit plan” means a group or individual policy of accident and health insurance, a subscriber contract of a group hospital service corporation operating under Chapter 842, or, to the extent required by federal law, an evidence of coverage issued by a health maintenance organization operating under Chapter 843 that is advertised, marketed, or designed primarily as a supplement to reimbursements under Medicare for the hospital, medical, or surgical expenses of an individual eligible for Medicare.
(b) A policy, contract, subscriber contract, or evidence of coverage is not considered to be a Medicare supplement benefit plan if it is:
(1) a policy, contract, subscriber contract, or evidence of coverage of one or more employers or labor organizations, or of the trustees of a fund established by one or more employers or labor organizations, or a combination, for employees or former employees, or a combination, or for members or former members, or a combination, of the labor organizations;
(2) a policy or health care benefit plan, including a policy or contract of group insurance, a group contract of a group hospital service corporation operating under Chapter 842, or a group evidence of coverage issued by a health maintenance organization operating under Chapter 843 that is not marketed or held to be a Medicare supplement benefit plan; or
(3) an individual or group evidence of coverage issued in accordance with a contract under Section 1833 or 1876, Social Security Act (42 U.S.C. § 1395l or 1395mm), by a health maintenance organization operating under Chapter 843.

(c) The commissioner by rule may modify the definition of “Medicare supplement benefit plan” provided by Subsection (a) to the extent necessary for this state to qualify as a state with an approved regulatory program.