Iowa Code § 504.712: Voting entitlement generally.

1. Except as provided in the articles of incorporation or bylaws, each member shall be entitled to one vote on each matter submitted to a vote of members.

2. Unless the articles or bylaws provide otherwise, if a membership stands of record in the names of two or more persons, the persons’ acts with respect to voting shall have the following effect:

a. If only one votes, such act binds all.

b. If more than one votes, the vote shall be divided on a pro rata basis.