When I started collecting nationals, I never thought I'd see a note on charter 4807 -- The FNB of Princeton, Minnesota. The bank lasted only 14 months, through the end of 1893, and had only $105 (21 $5 brownbacks, to be precise) outstanding in 1910. Princeton is one of the core towns in my collecting area.
As luck would have it, George Newbert -- the assistant cashier of the bank -- saved an entire uncut sheet of notes just before the bank closed. It was passed down to one of his daughters, and at some point the top note was cut from the sheet. Later, the notes were passed down another generation, and they were sold as a three note sheet to a coin dealer, and then to auction with Heritage. At some point the sheet was cut and the notes graded by PCGS.
The first of the four notes from this sheet to be sold publicly was the A-plate note, from the Melamed Collection auction in August 2010. I didn't know that any more notes from the sheet existed; however, there were hints that this note had siblings. The first clue was that this high grade had a horizontal fold near the bottom, suggesting it may have been folded as part of a sheet. Another was that the note sold for far less than my expectations -- apparently there was information out there that more of these are around. Sure enough, a few months later, the B-plate note showed up in the FUN sale. And then another in each of the next two Heritage sales -- four notes in all, to come to auction in about 15 months.