This isn't much of an issue for traders That's a nice benefit of having 40+ trading venues in the US. They had problems at the open as well with connectivity on one of their gateways. Issues like this crop up all the time and most of the time they are resolved before the open. The good news is that they aren't reporting any lost trades or trade busts yet so this isn't as bad as the BATS open at BATS:) Having said tha…
Are there serious trading shops that don't route orders dynamically to multiple venues?
Most funds just trade through an intermediary like GS and all intermediaries have SOR's that route to each venue in the US as per RegNMS
The remaining 10% are your market makers and HFT's and for them this is a bit of a headache but it happens and they are well equipped to deal with this. No fund that I know of is a market maker for just the NYSE, but if there is then I guess they just go home early?