As used in sections 376.891 to 376.894, the following terms mean:
(1) "Certificate holder", a person who receives health care benefits or services pursuant to a policy, contract or plan;
(2) "Plan administrator":
(a) The person designated as the plan administrator by the instrument under which the contract or plan is operated; or
(b) If no plan administrator is designated, the plan sponsor;
(3) "Policy, contract or plan", a group insurance policy providing health care coverage on an expense incurred basis, a group service or indemnity contract issued by a not-for-profit health services corporation, a health maintenance organization plan or a self-insured group health benefit plan of any type or description.