Md. Code, Alcoholic Beverages and Cannabis § 4-1102

(a) (1) An individual in a restaurant, club, or hotel for which a Class B or Class C license allowing the sale of wine is issued may consume wine not purchased from or provided by the license holder only if:

(i) the wine is consumed with a meal during the hours of sale specified by the license;

(ii) the individual obtains the approval of the license holder;

(iii) the wine is not available for sale on the license holder’s wine list; and

(iv) the license holder obtains a permit from the local licensing board before allowing an individual the privilege of consuming wine not purchased from or provided by the license holder.

(2) A license holder may not allow an individual who is under the age of 21 years or who is visibly under the influence of an alcoholic beverage the privilege of consuming the wine.

(b) (1) A local licensing board shall issue a permit at no charge to each license holder who seeks to allow an individual to consume wine under the conditions set out in subsection (a)(1) of this section.

(2) A license holder that obtains the permit may determine and charge the individual a fee for the privilege, on which a sales tax applicable to alcoholic beverages shall be imposed.

(c) (1) Except as provided in paragraph (2) of this subsection, the license holder shall dispose of the wine that remains after the meal is finished.

(2) An individual may remove from the licensed premises a bottle of wine, the contents of which are partially consumed with the meal, if the license holder or an employee of the license holder inserts a cork in or places a cap on the bottle.

(3) A bottle of wine that is removed from the licensed premises under paragraph (2) of this subsection is an “open container” for purposes of § 10–125 of the Criminal Law Article.