Section 193.631 - Restriction on transfer or registration of membership interests(1) HOW IMPOSED. A restriction on the transfer, including registration, of a membership interest may be imposed in the articles, in the bylaws, in a member control agreement, by a resolution adopted by the members, or by an agreement among or other written action by members or among them and the cooperative. A restriction imposed by a member control agreement or other written action of members is effective only against the parties to the agreement or written action or the members who assent pursuant to a member resolution. A restriction is not binding with respect to membership interests issued prior to the adoption of the restriction, unless the holders of those membership interests are parties to the agreement or voted in favor of the restriction.(2) RESTRICTIONS PERMITTED. (a) A restriction under sub. (1) is enforceable only if the restriction is not manifestly unreasonable under the circumstances and any of the following apply: 1. The restriction is noted conspicuously on a certificate of membership interest representing the membership interest or the existence of the restriction is noted on the certificate and reference is made to a separate document creating or describing the restriction.2. The restriction is imposed under this chapter or is included in the articles or bylaws.3. The restriction relates to an uncertificated membership interest and is included in information sent to the holders of such a membership interest.(b) A restriction that is enforceable under par. (a) may be enforced against the holder of the restricted membership interest or a successor or transferee of the holder, including a pledgee or a legal representative.