Md. Code, Corps. & Ass'ns § 9A-1108

(a) In addition to any other activities which may not constitute doing business in this State, for the purposes of this subtitle, the following activities of a foreign limited liability partnership do not constitute doing business in this State: (1) Maintaining, defending, or settling an action, suit, claim, dispute, or administrative or arbitration proceeding; (2) Holding meetings of its partners or agents or carrying on other activities that concern its internal affairs; (3) Maintaining bank accounts; (4) Conducting an isolated transaction not in the course of a number of similar transactions; (5) Foreclosing mortgages and deeds of trust on property in this State; (6) As a result of default under a mortgage or deed of trust, acquiring title to property in this State by foreclosure, deed in lieu of foreclosure, or otherwise; (7) Holding, protecting, renting, maintaining, and operating property in this State so acquired; or (8) Selling or transferring title to property in this State so acquired to any person, including the Federal Housing Administration or the Veterans Administration. (b) In addition to any other activities which may constitute doing business in this State, for the purposes of this subtitle any foreign limited liability partnership which owns income producing real or tangible personal property in this State, other than property exempted by subsection (a) of this section, shall be considered to be doing business in this State.