Iowa Code § 174.20: Fraudulent entries of horses.

A person shall not knowingly enter or cause to be entered any horse of any age or sex under an assumed name, or out of its proper class, to compete for any purse, prize, premium, stake, or sweepstake offered or given by any person in the state, or drive any such horse under an assumed name, or out of its proper class, where such prize, purse, premium, stake, or sweepstake is to be decided by a contest of speed.