C.R.S. § 13-80-109

Except for causes of action arising out of the transaction or occurrence which is the subject matter of the opposing party’s claim, the limitation provisions of this article shall apply to the case of any debt, contract, obligation, injury, or liability alleged by a defending party as a counterclaim or setoff. A counterclaim or setoff arising out of the transaction or occurrence which is the subject matter of the opposing party’s claim shall be commenced within one year after service of the complaint by the opposing party and not thereafter.