Maryland Corporations and Associations Section 4-201

      (a)      A corporation may elect to be a close corporation under this title by including in its charter a statement that it is a close corporation.

      (b)      The statement that a corporation is a close corporation shall be:

            (1)      Contained in the articles of incorporation originally filed with the Department; or

            (2)      Added to the charter by an amendment which is approved:

                  (i)      Under the provisions of § 2-603 of this article, if at the time of the adoption of the amendment no stock of the corporation is either outstanding or subscribed for; or

                  (ii)      By the affirmative vote of every stockholder and every subscriber for stock of the corporation.