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Rare Dual Serial Number Error Discovered

Collector finds the rare error on a $5 Federal Reserve bank note heading to auction on June 26.
Dual Serial Error

Numismatic detectives might call it a case of the missing serial numbers, but one strange $5 Federal Reserve bank note is claiming fame for much more than just that. Collector Alex Allis recently found this bizarre note that is also boasting a mismatched serial number and the experts determined this to be a discovery of sensational proportions.

“Errors like this simply don’t turn up every day,” said Stephanie Sabin, PCGS president. “Our graders were stunned when they found this remarkable error come through.”

“I was a coin collector for many years,” explains Allis, who said she began poring through bank notes during the pandemic when coin shortages stemmed the flow of coinage for her to search through. “Banks would give a thousand $1 bills but not a single roll of coins. I kept my dollar bills I received from change in a separate box, but when I was putting the $5 into the box it demanded my immediate attention.”

She recalls this error specimen feeling to the touch just like a brand-new bill might. “I looked at it about a thousand times. I checked all the usual signs of authenticity for bills.” She adds, “Of course, I didn’t sleep that night!”

Allis says that throughout the pandemic she tried sparking an interest in her kids that might lead to them studying and collecting coins and bank notes. “Although I have had coins and currency put away, the pandemic reminded all of us how fragile life is – and how would my children know what to do with my collection?” She goes on to say, “They are totally engaged now!”

Nearly a decade ago, the Bureau of Engraving and Printing (BEP) introduced new, state-of-the-art bank note production equipment meant to increase output and tighten quality control. large examining and printing equipment (LEPE systems, as they are known, were installed at both BEP facilities to augment decades-old currency overprinting and processing equipment (COPE) system capacity. This subject $5 error bank note is a product of the relatively novel LEPE system, which had just recently been approved for production of the $5 denomination in 2019.

With new technology comes new potential for the generation of exotic and mysterious mistakes, as evidenced right here. Research into the complicated technical specifics that caused the error continues, although it has been established that a LEPE system setup issue was fundamentally to blame. While it is not yet certain whether that configuration problem was digital or mechanical, accidental, or intentional, or something else entirely, what remains wholly clear is that this $5 error type is guaranteed to induce jaw-dropping, breathtaking, and head-scratching reactions everywhere it goes.

This rare note is going up for auction on June 26 at GreatCollections. More information can be found on their website at