Md. Code, Commercial Law § 13–317

(a) Except as provided in subsection (b) of this section, as a condition of accepting a credit card or device as payment for consumer credit, goods, realty, or services, a person may not record the address or telephone number of the credit card holder.

(b) A person may record the address or telephone number of a credit card holder if:

(1) The information is necessary for:

(i) The shipping, delivery, or installation of consumer goods; or

(ii) Special orders of consumer goods or services;

(2) Authorization from the credit card issuer as to the availability of credit is not required by the issuer to complete the credit card transaction; or

(3) The person processes credit card transactions by mailing transaction forms to a designated bankcard center for settlement.

(c) A person accepting a credit card or device as payment for consumer credit, goods, realty, or services may request that the credit card holder display a form of identification.