It's a public serial that wasn't added to the Public Serial account yet.simpsonspedia.net wrote: ↑Mon Feb 15, 2021 8:59 pmhttps://de.eurobilltracker.com/notes/?id=100389149
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public note? are the printer codes suspicious?
Up to 2011, Vidorial (the name of the first EBTor who registered this note) was a German-language Internet platform creating video tutorials in the TI area. It was run by the German media outlets Computer Bild / CDA Verlag. They were apparently based in Perg, Austria, though.
On the 19th of September, 2011 (3 weeks after registering the note on EBT), they published a video about EuroBillTracker on their YouTube channel, showing @ 1:31 how they entered that particular note in EBT. On the same video, you can see how they created and EBT account, and they also show in detail how they entered their second note (including fully disclosed serial number and printer code). Curiously, that second note never made a hit.

BeatBox (second EBTor registering this note, and registering a total of only 4 notes), and Tupac (who had the only other hit with BeatBox, out of 2 notes registered in total) are most likely journalists or colleagues at Vidorial. They're both from Bickenbach (Hessen), Germany.
I won't publish the video link here, because this is a public forum.