Section 204(a)(9) of the California Corporations Code allows the articles of incorporation to include a provision requiring the approval of the shareholders (Section 153) or the approval of the outstanding shares (Section 152) for any corporate action, even though not otherwise required by the General Corporation Law.   In 1983, the Business Law Section of the California State Bar sponsored legislation that permits the articles to include a provision requiring a minority vote (i.e., a vote of a specified percentage or proportion of the outstanding shares of the class or series that is less than a majority of the class or series to approve any corporate action) notwithstanding Section 204(a)(9).  1983 Cal. Stats. ch. 1223. 

This type of provision is permitted only with respect to shares designated as "preferred" or "preference shares".  Cal. Corp. Code §  402.5.  However, this is a meaningless requirement.  The designation is merely the name assigned to a class or series of shares.  Designating shares as "preferred" does not make them so.  Section 176 of the Corporations Code apophatically defines "preferred shares" as shares other than "common shares".  As to what makes shares "common shares," see this post.