(This section on the counterfeit $5 notes is the result of research by Robert Perigoe. This information originally appeared in the December 2012 issue of the Journal of the U. S. Mexican Numismatic Association.)

All of the counterfeit five peso notes so far encountered have been from Series 2. Perigoe lists the six crudest ones, and then finishes with two known (and one suspected) of the most sophisticated that almost certainly have been illicitly fashioned from unissued remainders.

Counterfeit $5 Estado de Sonora note Type 1

Est Sonora 5 2 4188

GENUINE	COUNTERFEIT
	All six of the crude types are patterned on printing position 2 and share one common aspect in the black printing on the front. The outer curve on the fan at the upper left corner is twice the width of the inner ones, whereas the curves should all be the same width.
	These types also can be distinguished by a common fault in the green printing on the back. The tail on the ‘R’ of ‘SONORA’ is curved, whereas it should be a straight diagonal line.
	The watermark, DEFIANCE BOND 1912, is sometimes found on these notes.
	On the front of the counterfeit, the tail on the ‘R’ of ‘SONORA’ is almost straight instead of having a pronounced curve.
	The Randall signature looks uniform enough to be made by a hand-stamp
	The Mountain Seal is undersized by 1mm in both height and width. It has no diagonal shading in the sky or water, has large colorless blotches in the water, and the only mark in the Liberty Cap is a small crescent. Ink colors of carmine and vermilion have both been observed
	On the counterfeit Eagle Seal, the eagle design is quite imaginative. There are distinct spots on the neck and breast where there should not be any, and the upper edge of the right wing is black instead of colourless
The right ball serif on the large blue '$' is parallel to the upright and the left ball serif is very nearly so.	Both ball serifs curve in well toward the upright

The circular of November 1914 lists the following indications for a counterfeit $5 Series 2 note, which closely resembles this Type 1.

GENUINE	COUNTERFEIT
	facsimile signature
	In seal eagle is completely black, snake is very thin and dark, laurel leaves are smaller and inverted
‘pagará’ and ‘México’ have accents	‘pagará’ and ‘México’ have no accent or they have been added by hand
	‘AL PORTADOR EN EFECTIVO CONFORME AL DECRETO NUM. 13 DE FECHA 27 DE AGOSTO DE 1913’ in smaller typeface
	In red seal, cap is incomplete and completely red, with only two light white rays, and lake has two large white smudges at the edges
	On reverse values and ‘ESTADO DE SONORA’ smaller