26 USC 5681 - Penalty relating to signs

(a) Failure to post required sign 
Every person engaged in distilled spirits operations who fails to post the sign required by section 5180 (a) shall be fined not more than $1,000, or imprisoned not more than 1 year, or both.
(b) Posting or displaying false sign 
Every person, other than a distiller, warehouseman, or processor of distilled spirits who has received notice of registration of his plant under the provisions of section 5171 (c), or other than a wholesale dealer in liquors who has paid the special tax (or who is exempt from payment of such special tax by reason of the provisions of section 5113 (a)), who puts up or keeps up any sign indicating that he may lawfully carry on the business of a distiller, warehouseman, or processor of distilled spirits, or wholesale dealer in liquors, as the case may be, shall be fined not more than $1,000, or imprisoned not more than 1 year, or both.
(c) Premises where no sign is placed or kept 
Every person who works in any distilled spirits plant on which no sign required by section 5180 (a) is placed or kept, and every person who knowingly receives at, or carries or conveys any distilled spirits to or from any such distilled spirits plant or who knowingly carries or delivers any grain, molasses, or other raw material to any distilled spirits plant on which such a sign is not placed and kept, shall forfeit all vehicles, aircraft, or vessels used in carrying or conveying such property and shall be fined not more than $1,000, or imprisoned not more than 1 year, or both.
(d) Presumption 
Whenever on trial for violation of subsection (c) by working in a distilled spirits plant on which no sign required by section 5180 (a) is placed or kept, the defendant is shown to have been present at such premises, such presence of the defendant shall be deemed sufficient evidence to authorize conviction, unless the defendant explains such presence to the satisfaction of the jury (or of the court when tried without jury).