Neb. Rev. Stat. § 25-331

(1)(a) A defending party may, as a third-party plaintiff, serve a summons and complaint on a nonparty: (i) Who is or may be liable to the defending party for all or part of the claim against the defending party; or (ii) Whose negligence was or may have been a proximate cause of the transaction or occurrence that is the subject matter of the plaintiff's claim and who is not precluded by section 25-21,185.11 from being made a party. (b) The third-party plaintiff shall, by motion, obtain the court's leave if the third-party plaintiff files the third-party complaint more than fourteen days after serving its original answer. (c) The person served with the summons and third-party complaint, hereinafter called the third-party defendant, has all the rights and obligations of a defendant, including those created by this section and by the rules promulgated by the Supreme Court pursuant to sections 25-801.01 and 25-1273.01 . (d) The third-party defendant may assert against the plaintiff any defense that the third-party plaintiff has to the plaintiff's claim. The third-party defendant may also assert against the plaintiff any claim arising out of the transaction or occurrence that is the subject matter of the plaintiff's claim against the third-party plaintiff. (e) The plaintiff may assert against the third-party defendant any claim arising out of the transaction or occurrence that is the subject matter of the plaintiff's claim against the third-party plaintiff. (f) A defending party may assert against the third-party defendant a claim that the third-party defendant is liable to the defending party for all or part of the claim against the defending party. (g) A third-party defendant may bring in a nonparty if subdivision (1)(a) of this section would allow a defending party to do so. (h) Any party may move to strike the third-party claim, to sever it, or try it separately. (2) When a claim is asserted against a plaintiff, the plaintiff may bring in a nonparty if subdivision (1)(a) of this section would allow a defending party to do so.