It sounds like NASDAQ is having a problem with the Tape C consolidated feed (which they administer). Here's some good places to watch for updates:<p><a href="http://www.nasdaqtrader.com/Trader.aspx?id=MarketSystemStatus" rel="nofollow">http://www.nasdaqtrader.com/Trader.aspx?id=MarketSystemStatu...</a><p><a href="http://markets.nyx.com/nyse/market-status" rel="nofollow">http://markets.nyx.com/nyse/market-status</a><p><a href="http://www.batstrading.com/alerts/" rel="nofollow">http://www.batstrading.com/alerts/</a><p><a href="https://www.directedge.com/Alerts.aspx" rel="nofollow">https://www.directedge.com/Alerts.aspx</a><p>edit: Notes for people trying to understand the jargon. The UTP SIP is the consolidated feed for Tape C (i.e. NASDAQ listed) securities. In this case, the feed is composed of two parts: UTDF and UQDF. The UTDF is a feed of last sale prices and the UQDF is the feed of the best quotes from the various U.S. equity exchanges. It sounds like the problem is with the quote feed (UQDF). That's why they've halted trading on NASDAQ listed equities at all the other exchanges.<p>These days almost everyone takes market data directly from each exchange and builds their own view of the market, so losing the consolidated feed wouldn't be a huge deal, except that it isn't clear what should happen to stay in compliance with Reg NMS when the consolidated feed is down.
Security flaws in financial institutions has got to be one of my greatest fears. Wall street doesn't understand software[0][1] yet they rely so heavily on it with algorithmic trading[2]. The day that something goes terribly wrong, they're going to have no idea what happened...<p>[0] <a href="http://www.wired.com/threatlevel/2008/09/six-year-old-st/" rel="nofollow">http://www.wired.com/threatlevel/2008/09/six-year-old-st/</a>
[1] <a href="http://www.vanityfair.com/business/2013/09/michael-lewis-goldman-sachs-programmer" rel="nofollow">http://www.vanityfair.com/business/2013/09/michael-lewis-gol...</a>
[2] <a href="http://www.ted.com/talks/kevin_slavin_how_algorithms_shape_our_world.html" rel="nofollow">http://www.ted.com/talks/kevin_slavin_how_algorithms_shape_o...</a>
For once, this headline understates the story. My first thought was "Why does this belong on hacker news" because they stop trading specific securities all the time. But a system crash is another thing.
"UPDATE 3: CNBC reports the Securities and Exchange Comission is monitoring the situation."<p>Wow, CNBC, what would we do without your valuable insight?