Shareholders are the persons who enjoy the most rights under the California General Corporation Law.  A "shareholder" is not just anyone with rights in the shares, Corporations Code Section 185 defines a "shareholder" as "a holder of record of shares".  Beneficial owners who do not hold of record have relatively few rights that the corporation is bound to respect.  As U.S. District Court Judge William Alsup has observed:

"California Corporation Code only acknowledges the right of beneficial owners in two situations: (1) beneficiary of an employment benefit plan or of any entity defined in Section 3(a) of the federal Investment Company Act of 1940 (Cal. Corp. Code 711) and (2) a shareholder derivative action (Cal. Corp. Code 800). 

Dux Capital Mgmt. Corp. v. Chen, 2004 U.S. Dist. LEXIS 22703, *18-19.  Judge Alsup's reference to Section 711 is to California's incomprehensible statute requiring the disclosure of voting records.  See California's Bizarre Voting Records Disclosure Requirement.  Although Section 800 bestows standing on beneficial owners in derivative cases, Judge Alsup declined "to extend the rights of beneficial ownership to direct actions".  The Ninth Circuit affirmed Judge Alsup sub nomine Davis v. Yageo Corp., 481 F.3d 661 (9th Cir. 2007).