In any case, in which the par value of the shares of stock of a corporation shall be required to be stated in the articles of incorporation, or any amendment thereto, or in any other place, it shall be stated in respect to shares without par value that such shares are without par value, and when the amount of such stock authorized, issued or outstanding shall be required to be stated, the number of shares thereof authorized, issued or outstanding, as the case may be, shall be stated, and it shall also be stated that such shares are without par value.
Iowa Code § 493.2