CERTAIN COORDINATION OF BENEFITS PROVISIONS PROHIBITED.

(a) A health benefit plan or vision benefit plan subject to this subchapter may not be delivered, issued for delivery, or renewed in this state if:

(1) a provision of the plan excludes or reduces the payment of benefits for eye care expenses to or on behalf of an enrollee;

(2) the reason for the exclusion or reduction is that eye care benefits are payable or have been paid to or on behalf of the enrollee under another plan; and

(3) the exclusion or reduction would apply before the full amount of the eye care expenses incurred by the enrollee and covered by both plans have been paid or reimbursed or the full amount of the applicable coverage limit of the plan containing the exclusion or reduction is reached.

(b) Nothing in this section requires a secondary plan issuer to pay an amount that, when added to a payment amount made by a primary plan issuer, would exceed the usual and customary billed charges of the health care provider.