Here is the MD law on the subjest:
§ 4-301. "Assault pistol" defined.
In this subtitle, "assault pistol" means any of the following firearms or a copy regardless of the producer or manufacturer:
(1) AA Arms AP-9 semiautomatic pistol;
(2) Bushmaster semiautomatic pistol;
(3) Claridge HI-TEC semiautomatic pistol;
(4) D Max Industries semiautomatic pistol;
(5) Encom MK-IV, MP-9, or MP-45 semiautomatic pistol;
(6) Heckler and Koch semiautomatic SP-89 pistol;
(7) Holmes MP-83 semiautomatic pistol;
(8) Ingram MAC 10/11 semiautomatic pistol and variations including the Partisan Avenger and the SWD Cobray;
(9) Intratec TEC-9/DC-9 semiautomatic pistol in any centerfire variation;
(10) P.A.W.S. type semiautomatic pistol;
(11) Skorpion semiautomatic pistol;
(12) Spectre double action semiautomatic pistol (Sile, F.I.E., Mitchell);
(13) UZI semiautomatic pistol;
(14) Weaver Arms semiautomatic Nighthawk pistol; or
(15) Wilkinson semiautomatic "Linda" pistol.
[An. Code 1957, art. 27, § 36H-1; 2002, ch. 26, § 2.]
§ 4-303. Assault pistols - Prohibited.
a) In general.- Except as provided in subsection (b) of this section, a person may not:
(1) transport an assault pistol into the State; or
(2) possess, sell, offer to sell, transfer, purchase, or receive an assault pistol.
(b) Exception.- A person who lawfully possessed an assault pistol before June 1, 1994 and who registered the assault pistol with the Secretary of the State Police before August 1, 1994 may continue to possess the assault pistol.
[An. Code 1957, art. 27, § 36H-3; 2002, ch. 26, § 2.]