Okla. Stat. tit. 23, § 23-13: Comparative negligence

In all actions hereafter brought, whether arising before or

after the effective date of this act, for negligence resulting in

personal injuries or wrongful death, or injury to property,

contributory negligence shall not bar a recovery, unless any

negligence of the person so injured, damaged or killed, is of

greater degree than any negligence of the person, firm or

corporation causing such damage, or unless any negligence of the

person so injured, damaged or killed, is of greater degree than the

combined negligence of any persons, firms or corporations causing

such damage.