I've been observing that thus far, in both MP and SP, station licenses only function as "discount coupons" for you. No docking fees, lower prices for buying AND selling (ie you get less if you sell to a licensed station).
The station does not "actively engage incoming hostiles". You can be docked (but have not clicked "Enter Station" yet), a red ship can fly inside and still shoot you. I have had this happen many times in both licensed and unlicensed stations as well as in those I built.
This is only in reference to the "protection" part of the station. You're as much protected in a licensed station as in an unlicensed one as far as I can see.
[Edited on 19-6-2013 by ELiTe]













