PMG -
The PMG team was able to spot this counterfeit with a good loupe and basic knowledge of the Bureau of Engraving and Printing's printing process.Before we begin diagnosing this error let's review how a US Federal Reserve Note is printed. The paper (or substrate) is made at Crane Currency and has been since 1861. The substrate gets delivered in large pallets. Each sheet can fit 32 or 50 notes (depending on the denomination and series). The sheets are then feed into a printing press with the backs being printed first. This is known as the First Print. The notes will then be put aside for a few days to dry. Once dry, the sheets will get their Second Print - the black ink the front of the note. Again, it will take a few days to dry. Lastly, the notes will get their overprints which includes the District seal, Treasury seal and serial numbers. After which the notes will go through a guillotine to get cut down into singles, followed by the bundling and packaging the notes so they are ready for shipment to banks.

Armed with this knowledge, we know that this error has been altered. "The United States of America" that is inverted was printed during the Second Print. The District seal was printed days later at a different station. There is no way that just "The United States of America" could be inverted without the rest of the Second Print also being inverted.
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