Joe
Your comparisons are excellent, but are incorrect is this respect: Christy & Jones was not chip makers. Burt made all C & J chips and used an edge spot punch that produced a rounded spot as you show in #1. I would think chip #2 is Paulson also because of the straight spot. Paulson is known to have used a number of different molds. I don't think Burt ever used a straight 1/2" spot, but I could be wrong?. Chip #3 is Paulson. One more thing, your comment should read: Christy & Jones made by Burt and two imposters and wannabees.
Jim