Md. Code Regs. 31.08.04.01
On and after the effective date of these regulations each insurer issuing a motor vehicle liability insurance policy covering a Maryland resident shall include in the policy a provision regarding out-of-State insurance coverage at least as favorable to the insured as the following:
"It is agreed that, subject to all the provisions of the policy except where modified herein, the following provision is added:
"If, under the provisions of the motor vehicle financial law or the motor vehicle compulsory insurance law or any similar law of the District of Columbia or of any state or province, a nonresident is required to maintain insurance with respect to the operation or use of a motor vehicle in such jurisdiction and such insurance requirements are greater than the insurance provided by the policy, the limits of the company's liability and the kinds of coverage afforded by the policy shall be as set forth in such law, in lieu of the insurance otherwise provided by the policy, but only to the extent required by such law and only with respect to the operation or use of a motor vehicle in such jurisdiction; provided that the insurance under this provision shall be reduced to the extent that there is other valid and collectible insurance under this or any other motor vehicle insurance policy. In no event shall any person be entitled to receive duplicate payments for the same elements of loss."
Md. Code Regs. 31.08.04.01