Md. Code Ann., Tax-Gen. § 9-208 — § 9-208

(a) The Comptroller may exempt a motor carrier from filing a motor carrier tax return if:
(1) the operations of the motor carrier are intrastate only;
(2) the intrastate commercial motor vehicles of the motor carrier are registered (tagged) by the Motor Vehicle Administration to operate within the State; and
(3) the exemption will not affect the enforcement of this subtitle adversely.
(b) A motor carrier is not required to report, on a motor carrier tax return, a commercial motor vehicle operated under a trip permit.