Md. Code, Commercial Law § 14–704

(a) Any person, his agent, or employee who sells or possesses with intent to sell a secondhand watch shall deliver to the buyer a written invoice which sets forth:

(1) The name and address of the seller;

(2) The name and address of the buyer;

(3) The date of the sale;

(4) The name of the watch or its maker;

(5) The serial number or, if none, any other distinguishing number or identification mark on the case and the movement of the watch; and

(6) Whether any serial number or any other distinguishing number or identification mark has been erased, defaced, removed, altered, or covered.

(b) The seller of a secondhand watch shall keep a duplicate of the invoice on file for at least one year from the date of the sale of the watch. The file shall be open for inspection during all business hours by the State’s Attorney of the county in which the seller engages in business.