Just a little theory I'm having. I've been privileged to be around that spot quite often in my RHA character and oh boy the kind of people you see there.
I'd say 2/3 of the sanctioned people have a connection one way or another to S-13 jump hole in NB. I wonder why. I bet 2/3 of the sanction reports are from there too.
It must the a-hole of the Sirius sector. Collecting all kinds of crap. Corsairs in Huntresses (more frequent by the day), revenge traders, OORP pirates, pvp lovers. It's a mad house really.
The more important question is what can be done about it? Frankfurt is starving because of it. I vote for it's closure come 4.85