That’s correct, the numbers should not be duplicated even when the notes are printed at different plants. But this was an administrative cock-up by the Bureau of Engraving & Printing (BEP). The BEP authorises particular serial number runs for exclusive use by one or other of its two printing plants in Washington DC or Forth Worth, Texas. They then intermittently release monthly reports after the print runs have been completed, documenting the actual serial numbers used.
Collectors began to get excited in early 2015 when the $1 Series of 2013 New York star notes printed in Washington, DC began to appear in circulation with serial numbers that weren’t listed in the published BEP production records. Responding to a Freedom of Information Act request in December 2015, the BEP admitted that serial number runs authorised for use by the Washington plant and printed in November and December of 2014 had been inadvertently omitted from their reports.
It wasn’t until the BEP’s June and July 2015 production records were released that the implications of the cock-up became apparent. Some (but not all) of the improperly documented serial numbers authorised for Washington had been unintentionally re-issued for use by the Fort Worth, Texas plant to print additional New York star notes. In total, the ‘overlapping’ serial numbers resulted in 6,650,000 pairs of notes having matching numbers.
The ’Project 2013B’ website linked above is a remarkable endeavour which potentially enables collectors with a singleton note from one or other of the plants to find its partner with a matching serial number and hugely increase the value for the pair. So, as things stand, the pair that you have should have a substantial value because there hasn’t yet been much ‘matching’.
But, here’s the rub. As I see it, the more matches that are achieved, the more the price will drop and there are an awful lot of duplicate serials out there which are yet to be paired up. My take would be that selling prices will progressively drop steeply as more matches are made, and so too will the value of pairs which might have been purchased at high prices in the ‘early days’. It sounds like you should attempt to sell as swiftly as possible, playing up the current ‘rarity’. Ebay, with a high reserve, might be as good a place as any.
Incidentally, since the ’discovery’ of these paired notes, there has been an issue with the likes of companies such as Paper Money Guaranty® (PMG®). Up until July last year they had refused to acknowledge these notes as “errors” and would only grade them as “duplicated serial numbers”. Under continued protest from someone who had a matching pair and with support from Dr. Frederick Bart (author of “United States Paper Money Errors”) PMG, at least, ultimately relented. Dr. Bart went on record in part with: “I endorse these as ‘Production Errors’ and believe they should be classified as Production Errors with Duplicated Serial Numbers. I intend to identify these as such, in the 5th Edition of United States Paper Money Errors.”
