Iowa Code § 214A.21: Advertising.

A person shall not knowingly do any of the following:

1. Advertise for sale any motor fuel that does not meet the standards provided in section 214A.2.

2. Falsely advertise for sale the quality, type, or kind of motor fuel or a component of motor fuel.

3. Add a coloring matter to the motor fuel which misleads a person who is purchasing the motor fuel about the quality of the motor fuel.

4. Falsely advertise for sale the classification of a motor fuel as provided in section 214A.2.