Iowa Code § 493.9: Change in stock.

Any such corporation may, by appropriate amendments to its articles of incorporation, adopted by a two-thirds affirmative vote of each class of stock then issued and outstanding and affected by such amendment, change its common or preferred stock having a par value to an equal, greater or less number of shares of stock having no par value, and, in connection therewith, may fix the amount of capital represented by such shares of stock without par value.