Me. Rev. Stat. tit. 12, § 6523

A person may not place any shack or temporary structure used for ice fishing on the frozen territorial waters or use the shack or structure, unless the owner's name and address are painted or otherwise clearly marked on the outside with 2-inch letters. A person who violates this section commits a civil violation for which a forfeiture of not less than $100 and not more than $500 may be adjudged.