I am afraid it has nothing to do with George Martin, more like HBO copyrights. If this was licensed then it would be shouted from rooftops, so in short -no they probably don't.
It doesn't stop any one however, as evidenced by various releases by various companies. If some one recasts these miniatures, the whole piracy argument will take a new curious twist.
very true! and your bang on about the recasters, seems a shame that the one who wrote and devised the series etc
doesn't get some sort if credit/roylty, but hey thats life I suppose
That's him alright 
