§ 601.4 Distinctive counterfeit deterrents.
Primary source
Verbatim text below is from the Electronic Code of Federal Regulations (eCFR), a public-domain U.S. government work. Always verify the current version with the eCFR before relying on it for any legal matter.
Full Text
The distinctive counterfeit deterrents that may be used in the denominations of United States Federal Reserve notes as prescribed by the Secretary of the Treasury are:
(a) Security threads containing graphics consisting of the designation “USA” and the denomination of the currency note, expressed in alphabetic or numeric characters.
(b) Optically variable inks with material characteristics.
(c) Non-visual characteristic inks with material characteristics.
(d) Optically variable thread (three-dimensional (3-D) security ribbon and micro-optic stripe) visible in front or back of the currency note.
(e) Non-visual characteristic features with material characteristics.
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