Md. Code, Bus. Reg. § 9A-501.1

(a) (1) This subsection does not apply to a person who: (i) sells construction materials other than materials involved in the installation of heating, ventilation, air–conditioning, or refrigeration equipment; and (ii) derives less than 25% of the person’s revenues from the sale of heating, ventilation, air–conditioning, or refrigeration equipment. (2) A person may not knowingly sell or offer to sell heating, ventilation, air–conditioning, or refrigeration equipment to another person, unless the individual purchasing the equipment: (i) holds a master license, a master restricted license, or a limited license or employs an individual who holds a master license, a master restricted license, or a limited license issued by the Board to provide or assist in providing heating, ventilation, air–conditioning, or refrigeration services; (ii) operates a business that resells heating, ventilation, air–conditioning, or refrigeration equipment to individuals licensed by the Board; or (iii) is not required to be licensed under § 9A–103 of this title. (b) A person that sells heating, ventilation, air–conditioning, or refrigeration equipment shall, at the time of sale, provide a written notice to the individual purchasing the equipment that contains information prescribed by the Board regarding the requirement that an individual be licensed by the Board before providing or assisting in providing heating, ventilation, air–conditioning, or refrigeration services in the State, including the installation of heating, ventilation, air–conditioning, or refrigeration equipment. (c) On or before January 1, 2026, the Board shall adopt regulations to carry out this section.