The Shareholders Protection Act shall not apply to any of the following:

(1) Unless the articles of incorporation provide otherwise, a business combination with an interested shareholder who was an interested shareholder immediately before April 9, 1988, unless the interested shareholder subsequently increased its ownership of the voting power of the outstanding voting stock of the issuing public corporation to a proportion in excess of the proportion of voting power that the interested shareholder owned immediately before April 9, 1988, excluding an increase approved by the board of directors of the issuing public corporation before the increase occurred;

(2) An issuing public corporation if the corporation's original articles of incorporation contain a provision expressly electing not to be governed by the act;

(3) An issuing public corporation if the corporation, by action of its board of directors, adopts an amendment to its bylaws within forty-five days of April 9, 1988, expressly electing not to be governed by the act, which amendment shall not be further amended by the board of directors;

(4) An issuing public corporation if the corporation does not have a class of voting stock that is listed on a national securities exchange or is authorized for quotation on an interdealer quotation system of a registered national securities association unless such circumstances result from action taken by an interested shareholder or a transaction in which a person becomes an interested shareholder;

(5) A business combination of an issuing public corporation with an interested shareholder which became an interested shareholder inadvertently and as soon as practicable divested sufficient shares so that the shareholder ceased to be an interested shareholder; or

(6) A business combination of an issuing public corporation with an interested shareholder which was an interested shareholder immediately before April 9, 1988, and inadvertently increased its ownership of the voting power of the outstanding voting stock of the issuing public corporation to a proportion in excess of the proportion of voting power that the interested shareholder owned immediately before April 9, 1988, if the interested shareholder divests itself of a sufficient amount of voting stock so that the interested shareholder is no longer the owner of a proportion of the voting power in excess of the proportion of voting power that the interested shareholder held immediately before April 9, 1988.