I have recently noticed a dramatic increase in the number of Bosnian banknotes of questionable authenticity appearing on
ebay. I have done a little research as to the detection of these notes, and from the little communications I have had with other advanced collectors, it appears these notes are originating from within Bosnia itself.
The notes in question are listed as P#6-9, the 2nd provisional issues.
Comparing notes from my own collection (both authentic & questionable), along with images from reputable dealers as well as those marketing the questionable notes, I have determined a fairly obvious design difference that makes it quite easy to distinguish them.
First, we have a note that is probably the most common of all of this series, which I purchased from a reputable dealer and am quite certain of its originality.

Notice the 2 squares that I have added (via PhotoShop).
#1. The tip of the wing of the dove is drawn out into a long single-stroke point.
#2. The hachek on the C in "Novcani" is rather flat and wide.
#3. (not shown) The R in "SERIES M" on the reverse has an almost vertical right leg.
Next, we compare the above points to one of the "questionable" notes.

#1. The tip of the wing has a much more blunt point.
#2. The hachek is much more angled.
#3. The right leg is at an obvious angle.
I have determined that these characteristics are common throughout the whole series.
*Note, I do not claim that these notes are counterfeit, only that they are questionable, as it is accepted that these notes are not found in UNC condition, as many of the "questionable" notes appearing on
ebay are. The going prices for these "questionable" notes often run in the $3-10 range, while the authentic notes from reputable dealers often sell in the $35-60 range. I do own a few of these "questionable" notes, and will probably attempt to get a complete set of both the "questionable" and authentic notes.