I have no idea what is happening. That is why I referenced the comments.
This appeared as an update on http://www.market-ticker.org/akcs-www?post=223800
“Update: It sounds like the Nasdaq has requested all other exchanges to stop all “Tape C” trade as well (that’s Nasdaq-listed securities.) One has to wonder if this is HFT-related (e.g. “caused” overloading) or whether this is some sort of actual failure.”
What do you make of “...stop all “Tape C” trade...”?
I am not a trader. I’d have to ask one.
Tape C is Nasdaq trades. Tape A is NYSE trades Tape B is AMEX The SIP data quoting server went down.