Colorado Revised Statutes Title 6. Consumer and Commercial Affairs § 6-2-108. Secret rebates or refunds prohibited

The secret payment or allowance of rebates, refunds, commissions, or unearned discounts, whether in the form of money or otherwise, or secretly extending to certain purchasers special services or privileges not extended to all purchasers upon like terms and conditions, to the injury of a competitor and where such payment or allowance tends to destroy competition, is an unfair trade practice. Any person, firm, partnership, corporation, or association resorting to such unfair trade practice commits a class 2 misdemeanor.