Mich. Comp. Laws § 450.3133: Classification.

Sec. 1133.

If a cooperative has classes of members pursuant to section 304, classification shall be based only on 1 or more of the following number of members, number of persons served, type of patronage, level of patronage, or whether or not members are patrons. In a consumer cooperative, classification of consumers by level of patronage shall not be used.