Okla. Stat. tit. 23, § 15

A. In any civil action based on fault and not arising out of contract, the liability for damages caused by two or more persons shall be several only and a joint tortfeasor shall be liable only for the amount of damages allocated to that tortfeasor. B. This section shall not apply to actions brought by or on behalf of the state. C. The provisions of this section shall apply to all civil actions based on fault and not arising out of contract that accrue on or after November 1, 2011.