(a) In this section, "shareholder" means:
(1) shareholders of a public benefit corporation that own, individually or collectively, at least two percent of the corporation's outstanding shares; or
(2) shareholders of a public benefit corporation the shares of which are listed on a national securities exchange that own at least the lesser of:
(A) the percentage of shares described by Subdivision (1); or
(B) shares whose market value is at least $2 million.
(b) A shareholder of a public benefit corporation may maintain a derivative action on behalf of the corporation to enforce compliance with the requirements of Section 21.956(a).