No, its not a special case. I have buys and sells on over two dozen stocks I watch on the L2 every single day. I have Etrade accounts and a fidelity account. The trades are sometimes routed through other market makers, sometimes not. But I always no who is handling a particular trade. I'm telling you it is commonplace. Now just because it is not showing does not mean I will not get the sell or buy, often that hidden bid or ask works to my advantage other times not.