Antlizzie; You have explained anonymous quite accurately. It is not one trading house. In fact if there were 500 trades in a day by 50 different houses and one of them was anonymous, chances are that 20 of the regular houses used the anonymous route at least once. I, personally have specified anonymous on at least a dozen trades in the last couple of years. Nothing nefarious, except that I wanted to keep my identity away from a couple of other traders that knew who I was by the house I was using. I do get a chuckle, though as everyone seems to categorize anonymous as one entity.
Regards
K