Idaho Code § 40-1904: Private and public notices.

Nothing contained in this chapter applies to any advertising display used exclusively for:

(1) Directional and other official signs and notices erected or maintained by public officers or agencies pursuant to and in accordance with direction or authorization contained in state or federal law, for the purpose of carrying out an official duty or responsibility;

(2) Structures, signs and displays advertising the sale or lease of property upon which they are located; and

(3) Structures, signs and displays advertising activities conducted on the property on which they are located.