(a) When a corporation purchases or redeems or otherwise acquires its own shares, the shares are restored to the status of authorized but unissued shares unless the articles prohibit their reissuance.
(b) If the articles prohibit the reissuance of shares upon their acquisition by the corporation, then upon the acquisition of those shares the authorized number of shares of the class and series, if any, to which the shares belonged is reduced by the number of shares acquired and the articles shall be amended to reflect the reduction in authorized shares. If all of the authorized shares of a class or series are acquired and their reissue is prohibited by the articles of incorporation, then the articles shall also be amended to eliminate any statement of rights, preferences, privileges, and restrictions relating solely to that class or series. Articles of amendment shall be filed within 60 days of the acquisition of the shares in accordance with the requirements of AS 10.06.512 - 10.06.514. Approval by the outstanding shares is not required to adopt such articles of amendment.