Are there any regulations that prohibit the utilization of currency (replica of a dollar bill) in advertising, e.g. oversized on a billboard.

Illustrations of Currency must be less than .75 or greater than 1.5 times actual size

If you need to actually cite the specific statute (18 U.S.C. 504) or get more detail, the citation and complete verbiage are set forth on this part of the Bureau of Printing & Engraving's site:

Reproducing Currency

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