Md. Code, Corporations and Associations § 4–202

(a) Clear reference to the fact that the corporation is a close corporation shall appear prominently:

(1) At the head of the charter document in which the election to be a close corporation is made;

(2) In each subsequent charter document of the corporation; and

(3) On each certificate representing outstanding stock of the corporation.

(b) The status of a corporation as a close corporation is not affected by the failure of any charter document or stock certificate to contain the reference required by this section.