Part III: Slot Machine Cheating · Physical Cheating Methods · #5.22

Bleached/Washed Bills

How it works

A counterfeiting technique specifically designed to defeat bill validators and counterfeit detection pens. The forger takes a low-denomination genuine bill ($1 or $5), dips it in a bleaching solution until all markings are removed, leaving only the blank genuine currency paper. The blank paper is then reprinted using a laser printer with a higher-denomination design ($100). Because the paper is genuine U.S. currency paper, it passes the “pen test” (iodine-based counterfeit detection pens) and feels authentic.

Where it appears

All bill-accepting devices, including slot machines, change machines, and kiosks.

On the record

The US Treasury, Federal Reserve and Secret Service cited $5 notes bleached and reprinted as $100s as a reason for the 2006 redesign of the $5 note, while saying such attempts did not pose a significant economic problem. The “superdollar” (or “supernote”) – a counterfeit $100 bill of such high quality that it was suspected to be produced by a foreign government – was a particular worry for authorities. When new counterfeits are found, bill validator makers issue firmware updates so machines reject them; one industry writer claims this can happen within days or even hours.

Published as a detection reference for surveillance, compliance and gaming-operations professionals. Thresholds and tuning are set by the property. Nothing here is instruction: the method is described so it can be recognised.