Iowa Code Title XII. Business Entities [Chs. 486-504C] § 501A.906. Restriction on transfer or registration of membership interests

a. A written restriction on the transfer or registration of transfer of membership interests of a cooperative that is not manifestly unreasonable under the circumstances may be enforced against the holder of the restricted membership interests or a successor or transferee of the holder, including a pledgee or a legal representative, if the restriction is any of the following:

b. Unless otherwise restricted by this chapter, the articles, bylaws, noted conspicuously on the face or back of the certificate, or included in information sent to the holders of uncertificated membership interests, a restriction, even though permitted by this section, is ineffective against a person without knowledge of the restriction. A restriction under this section is deemed to be noted conspicuously and is effective if the existence of the restriction is stated on the certificate and reference is made to a separate document creating or describing the restriction.