Okla. Stat. tit. 18, § 1126
In any derivative suit instituted by a shareholder of a corporation, it shall be averred in the petition that the plaintiff was a shareholder of the corporation at the time of the transaction of which he complains or that his stock thereafter devolved upon him by operation of law.
Laws 1986, HB 1979, c. 292, § 126, eff. November 1, 1986.