Delaware Code (Titles 8, 9, 25, 30)
8 Del. C. § 202 — Restrictions on transfer and ownership of securities
(a)
A written restriction or restrictions on the transfer or registration of transfer of a security of a corporation, or on the amount of the corporation’s securities that may be owned by any person or group of persons, if permitted by this section and noted conspicuously on the certificate or certificates representing the security or securities so restricted or, in the case of uncertificated shares, contained in the notice or notices given pursuant to § 151(f) of this title, may be enforced against the holder of the restricted security or securities or any successor or transferee of the holder including an executor, administrator, trustee, guardian or other fiduciary entrusted with like responsibility for the person or estate of the holder. Unless noted conspicuously on the certificate or certificates representing the security or securities so restricted or, in the case of uncertificated shares, contained in the notice or notices given pursuant to § 151(f) of this title, a restriction, even though permitted by this section, is ineffective except against a person with actual knowledge of the restriction.
(b)
A restriction on the transfer or registration of transfer of securities of a corporation, or on the amount of a corporation’s securities that may be owned by any person or group of persons, may be imposed by the certificate of incorporation or by the bylaws or by an agreement among any number of security holders or among such holders and the corporation. No restrictions so imposed shall be binding with respect to securities issued prior to the adoption of the restriction unless the holders of the securities are parties to an agreement or voted in favor of the restriction.
(c)
A restriction on the transfer or registration of transfer of securities of a corporation or on the amount of such securities that may be owned by any person or group of persons is permitted by this section if it:
(d)
Any restriction on the transfer or the registration of transfer of the securities of a corporation, or on the amount of securities of a corporation that may be owned by a person or group of persons, for any of the following purposes shall be conclusively presumed to be for a reasonable purpose:
(e)
Any other lawful restriction on transfer or registration of transfer of securities, or on the amount of securities that may be owned by any person or group of persons, is permitted by this section.
Source: official text